Multimode couplers for quantum gates

Abstract

Techniques and couplers for managing coupling between qubits are presented. The coupler can be connected between a first qubit and a second qubit. The coupler can include three Josephson junctions (JJs). The first and second JJs can be symmetric, which facilitates the creation of a first mode of oscillation and a second mode of oscillation opposite to the first mode. The third JJ facilitates splitting between the first and second modes. The activation status of a ZZ gate between the first and second qubits can be controlled based on the excitation status of the first mode and the relationship between the first and second modes, where the excitation status is based on whether a pulse is applied to the coupler. When no pulse is applied, the ZZ gate is inactive and no coupling exists. When a pulse is applied, the first mode is excited, the ZZ gate is activated, and coupling exists between the qubits.

Description

[Background technology]

[0001] The present disclosure relates to quantum circuits, and more particularly to multi-mode couplers for quantum gates. A quantum computer may include a group of qubits that can perform quantum operations on data. A quantum circuit may include qubits, Josephson junctions, couplers, resonators, capacitors (e.g., qubit shunt capacitors and / or other capacitors), inductors, waveguides, and / or other quantum circuit components, quantum circuit elements, or circuits. Couplers may be utilized to enable qubit-to-qubit interaction or coupling between a pair of qubits via a quantum logic gate. For example, with respect to some existing coupling techniques, a capacitor may be between two transmon-type qubits, and the capacitor may be utilized as a coupler. When the qubits are detuned from each other in frequency space, the capacitor acting as a coupler may help provide always-on ZZ coupling.

[0002] The above background discussion is intended only to provide a contextual overview of quantum circuits and couplers and is not intended to be exhaustive. Summary of the Invention

[0003] The following presents a summary to provide a basic understanding of one or more embodiments of the disclosed subject matter. This summary is not intended to identify key or critical elements or to delineate the scope of any particular embodiments or the claims. Its sole purpose is to present concepts in a simplified form as a prelude to the more detailed description that is presented later. In one or more embodiments described herein, systems, devices, structures, methods, apparatus, and / or computer program products are presented that can facilitate the creation and / or use of couplers that can manage interaction and coupling between qubits.

[0004] According to an embodiment, a device may include a first electronic element and a second electronic element. The device may also include a coupler component connected to the first electronic element and the second electronic element, where the coupler component may include a first Josephson junction, a second Josephson junction, and a third Josephson junction associated with the first Josephson junction and the second Josephson junction in a quantum circuit, and the coupler component may have a first mode of oscillation and a second mode of oscillation based on the relationship between the first Josephson junction, the second Josephson junction, and the third Josephson junction in the quantum circuit. Such an embodiment of a device may provide several advantages, including that the device may enhance the efficiency and reliability of coupling between electronic elements.

[0005] In some embodiments, a geometry between the first Josephson junction and the second Josephson junction in the quantum circuit causes the first mode to have a first sign of coupling and the second mode to have a second sign of coupling, the second sign being opposite to the first sign, with respect to the first electronic element and the second electronic element. In particular embodiments, the first Josephson junction and the second Josephson junction may be substantially similar. The first Josephson junction may be located between a first capacitive pad and a third capacitive pad, the second Josephson junction may be located between a second capacitive pad and the third capacitive pad, and the third Josephson junction may be located between the third capacitive pad and a ground element. In some embodiments, a first frequency associated with the first mode or a second frequency associated with the second mode may be defined based on a parameter associated with the third Josephson junction and a geometry between the first Josephson junction, the second Josephson junction, and the third Josephson junction in the quantum circuit. Such embodiments of the device may provide several advantages, including that the device may desirably enhance the efficiency and reliability of coupling between electronic elements, increase the activation speed of coupler components to provide a desirably fast ZZ gate, and reduce the amount of power consumed in connection with coupling of electronic elements.

[0006] According to another embodiment, a device may include a coupler component that may be associated with a first quantum component and a second quantum component. The coupler component may include a Josephson junction and a resonator associated with the Josephson junction, where the Josephson junction may be associated with a first mode of oscillation and the resonator may be associated with a second mode of oscillation. Such an embodiment of a device may provide several advantages, including that the device may enhance the efficiency and reliability of coupling between quantum components.

[0007] In certain embodiments, the resonator may be a Lambda / 4 type resonator, and the first mode may be associated with a first sign of coupling and the second mode may be associated with a second sign of coupling, with respect to the first quantum component and the second quantum component, the second sign may be different from the first sign. Such embodiments of the device may provide several advantages, including that the device may desirably enhance the efficiency and reliability of coupling between quantum components, increase the activation speed of coupler components to provide a desirably fast ZZ gate, and reduce the amount of power consumed in connection with coupling of quantum components.

[0008] According to yet another embodiment, a method may include controlling excitation of a first vibrational mode of a coupler device based on whether a pulse is applied to the coupler device, where the coupler device may have the first vibrational mode and a second vibrational mode that is opposite to the first vibrational mode, and the coupler device may be electrically connected between a first quantum component and a second quantum component. The method may also include controlling creation of a ZZ gate between the first quantum component and the second quantum component based on the controlling of the excitation of the first vibrational mode. Such an embodiment of the method may provide several advantages, including that the method may enhance efficiency and reliability of coupling between quantum components.

[0009] In some other embodiments, the method may include applying the pulse to the coupler device and, in response to applying the pulse to the coupler device, creating the excitation of the first vibrational mode of the coupler device. The method may further include, in response to creating the excitation of the first vibrational mode, creating the ZZ gate between the first quantum component and the second quantum component. In yet other embodiments, the method may include, in response to no pulse being applied to the coupler device, suppressing ZZ interaction or coupling between the first quantum component and the second quantum component. Such other embodiments of the method may provide several advantages, including that the method may desirably enhance the efficiency and reliability of coupling between quantum components, increase the activation speed of coupler components to provide a desirably fast ZZ gate, and reduce the amount of power consumed in connection with coupling of quantum components.

[0010] According to yet another embodiment, a system may include a first qubit and a second qubit. The system may also include a coupler device that may be associated with the first qubit and the second qubit. The coupler device may have a first mode of oscillation and a second mode of oscillation. An activation status of a ZZ gate between the first qubit and the second qubit may be managed based on an excitation status of the first mode and a relationship between the first mode and the second mode, the excitation status being based on whether a pulse is applied to the coupler device. Such an embodiment of a system may provide several advantages, including that the system may enhance the efficiency and reliability of coupling between qubits.

[0011] In some embodiments, the pulse may be a radio frequency pulse, and in response to the radio frequency pulse being applied to the coupler device, the first mode may be excited. Based on the first mode being excited, the ZZ gate between the first qubit and the second qubit may be activated, and ZZ interaction or coupling between the first qubit and the second qubit may be enabled. In particular embodiments, in response to no pulse being applied to the coupler device, the first mode and the second mode may be in a non-excited state. Based on the first mode and the second mode being in a non-excited state, the ZZ gate may be inactive, and ZZ interaction or coupling between the first qubit and the second qubit may be suppressed.

[0012] In certain embodiments, the coupler device may include a first Josephson junction, a second Josephson junction, and a third Josephson junction associated with the first Josephson junction and the second Josephson junction in a circuit. The first mode and the second mode may be based on substantial symmetry between the first Josephson junction and the second Josephson junction and may be based on a parameter associated with the third Josephson junction. Based on the substantial symmetry between the first Josephson junction and the second Josephson junction, the first mode may have a first sign of coupling and the second mode may have a second sign of coupling, with respect to the first qubit and the second qubit, the second sign may be opposite to the first sign.

[0013] In another embodiment, the coupler device may include a Josephson junction and a Lambda / 4 resonator. The Josephson junction may be associated with the first oscillation mode and the Lambda / 4 resonator may be associated with the second mode. For the first qubit and the second qubit, the first mode may be associated with a first sign of coupling and the second oscillation mode may be associated with a second sign of coupling, the second sign being opposite to the first sign.

[0014] Such an embodiment of the system may provide several advantages, including that the device may desirably enhance the efficiency and reliability of coupling between qubits, increase the activation speed of coupler components to provide desirably fast ZZ gates, and reduce the amount of power consumed in connection with coupling qubits.

[0015] According to yet another embodiment, a system may include a coupler component that may be associated with a first electronic element and a second electronic element. The coupler component may include a first coupler element and a second coupler element. The coupler component may have a first mode associated with a first frequency and a second mode associated with a second frequency, and based on the relationship between the first coupler element and the second coupler element, the second mode may be capable of being an inverse of the first mode. Such an embodiment of a system may provide several advantages, including that the system may enhance the efficiency and reliability of coupling between electronic elements.

[0016] These and other features will become apparent from the following detailed description of illustrative embodiments thereof, which is to be read in connection with the accompanying drawings. [Brief explanation of the drawings]

[0017] [Figure 1]FIG. 1 shows a block diagram of one example of a non-limiting system that may include a coupler component that may manage interaction or coupling between qubits, in accordance with various aspects and embodiments of the disclosed subject matter.

[0018] [Figure 2] FIG. 1 illustrates a schematic diagram of one example of a non-limiting system that may utilize a multi-Josephson junction configuration and may include a coupler component (e.g., a facemon coupler component) that may manage the interaction or coupling between qubits, in accordance with various aspects and embodiments of the disclosed subject matter.

[0019] [Figure 3] FIG. 1 illustrates a diagram (e.g., a quantum circuit layout diagram) of one example of a non-limiting system that may utilize a multi-Josephson junction configuration and may include coupler components that may manage interaction or coupling between qubits, in accordance with various aspects and embodiments of the disclosed subject matter.

[0020] [Figure 4] FIG. 1 shows a diagram of one example of a non-limiting system that may utilize a multi-Josephson junction configuration and may include a tunable coupler component that may manage the interaction or coupling between qubits, in accordance with various aspects and embodiments of the disclosed subject matter.

[0021] [Figure 5] 10A-10D present exemplary graphical illustrations of simulations of a facemon coupler component when the frequency associated with the facemon coupler component exceeds the frequency associated with the qubit, in accordance with various aspects and embodiments of the disclosed subject matter.

[0022] [Figure 6]FIG. 10 illustrates an example graph of a simulation of a facemon coupler component when the frequency associated with the facemon coupler component is below the frequency associated with the qubit, in accordance with various aspects and embodiments of the disclosed subject matter.

[0023] [Figure 7] FIG. 1 illustrates a schematic diagram of one example of a non-limiting system that may utilize a Josephson junction and resonator configuration and may include a coupler component that may manage the interaction or coupling between qubits, in accordance with various aspects and embodiments of the disclosed subject matter.

[0024] [Figure 8] FIG. 1 illustrates a diagram (e.g., a quantum circuit layout diagram) of one example of a non-limiting system that may utilize a Josephson junction and resonator configuration and may include a coupler component that may manage interaction or coupling between qubits, in accordance with various aspects and embodiments of the disclosed subject matter.

[0025] [Figure 9] FIG. 1 shows a block diagram of one example of a non-limiting system that may utilize a Josephson junction and resonator configuration and may include a tunable coupler component that may manage the interaction or coupling between qubits, in accordance with various aspects and embodiments of the disclosed subject matter.

[0026] [Figure 10] 10A-10C present exemplary graphical illustrations of simulations of ground state coupling of coupler components that may utilize Josephson junction and resonator configurations in accordance with various aspects and embodiments of the disclosed subject matter.

[0027] [Figure 11] 10A-10C illustrate exemplary graphs of simulated gate speeds for coupler components that may utilize Josephson junction and resonator configurations in accordance with various aspects and embodiments of the disclosed subject matter.

[0028] [Figure 12] FIG. 1 illustrates a block diagram of an exemplary system that may be utilized to create, form, or design a device including qubits, coupler components, and / or other quantum components, elements, or circuits in accordance with various aspects and embodiments of the disclosed subject matter.

[0029] [Figure 13] FIG. 1 illustrates a flow diagram of one example of a non-limiting method that may control coupling between a first quantum component and a second quantum component, according to various aspects and embodiments of the disclosed subject matter.

[0030] [Figure 14] FIG. 1 illustrates a flow diagram of one example of a non-limiting method that may utilize a multi-Josephson junction coupler component that may control coupling between a first qubit and a second qubit, in accordance with various aspects and embodiments of the disclosed subject matter.

[0031] [Figure 15] FIG. 1 illustrates a block diagram of an example non-limiting operating environment capable of facilitating one or more embodiments described herein. DETAILED DESCRIPTION OF THE INVENTION

[0032] The following detailed description is merely exemplary and is not intended to limit the embodiments and / or their application or uses, nor is it intended to be bound by any expressed or implied information presented in the preceding Background or Summary sections or in the Detailed Description section.

[0033] One or more embodiments are now described with reference to the drawings, wherein like reference numerals are used to refer to like elements throughout. In the following description, for purposes of explanation, numerous specific details are set forth in order to provide a more thorough understanding of one or more embodiments. It will be apparent, however, that in various instances one or more embodiments may be practiced without these specific details.

[0034] A quantum computer may comprise a group of qubits that can perform quantum operations on data. In a quantum circuit comprising qubits, couplers may be used to enable inter-qubit interaction or coupling between pairs of qubits to create quantum logic gates. For example, a capacitor may be between two transmon qubits, and the capacitor may be used as a coupler. If the qubits are detuned from each other in frequency space, the capacitor acting as a coupler may help provide always-on ZZ coupling. By operating with a sufficiently large qubit-qubit detuning, this always-on coupling can be made small enough to be usable, but such couplers may be unnecessarily inefficient. Furthermore, ZX (e.g., cross-resonance) or ZZ (e.g., sizzle) gates may be activated using suitable microwave drive.

[0035] Another existing technique for coupling qubits may involve when the qubits are flux-tunable. With flux-tunable qubits, the coupling between a pair of flux-tunable qubits may be tuned by changing the frequencies of the qubits. Yet another existing approach is to use a resonator as a coupler. By exciting the resonator, a resonator-induced phase (RIP) gate may be performed between a pair of qubits.

[0036] Existing flux-tuned gates can typically have relatively better performance than existing microwave-driven gates and existing RIP gates. Existing RIP gates can be relatively limited in performance due to having to drive gates detuned far from the coupler frequency or having to use very long pulses to create closely detuned pulses. However, such existing couplers can utilize undesirable (e.g., inefficient, unsuitable, or suboptimal) amounts of power, can have unnecessarily slow activation resulting in slower gates, and / or can suffer other types of drawbacks, making existing couplers and coupler approaches unnecessarily inefficient and / or otherwise lacking in performance.

[0037] It may be desirable to enhance (e.g., increase, improve, or optimize) the efficiency, reliability, and performance of coupler components and reduce the amount of power consumed in connection with coupling qubits. It may also be desirable to enhance management of interactions and coupling between qubits. It may also be desirable to manage interactions and coupling between qubits without having to detune the coupler. It may also be desirable to increase the activation speed of couplers to provide desirably fast gates for coupling.

[0038] The disclosed subject matter includes coupler components and techniques that may have several advantages and overcome various drawbacks of existing coupler and coupling techniques. The disclosed coupler components and techniques for coupling qubits may have enhanced efficiency, reliability, and performance compared to existing couplers and techniques, may enhance management of interactions and coupling between qubits, and may reduce the amount of power consumed in connection with managing qubit coupling. The disclosed coupler components and techniques for coupling qubits may desirably manage qubit coupling without requiring coupler detuning. The disclosed coupler components and techniques for coupling qubits may also desirably increase the activation speed of such coupler components compared to existing couplers and techniques, providing desirably fast gates for coupling.

[0039] To that end, various embodiments described herein relate to techniques for managing coupling between qubits. A coupler component may be between and associated with (e.g., connected to) a first qubit and a second qubit in a quantum circuit. The coupler component may manage ZZ gates, interactions, and / or couplings between the first qubit and the second qubit. In particular embodiments, the qubits may be transmon qubits. A ZZ gate may relate to the frequency of one qubit being dependent on the frequency state of another qubit and whether the other qubit is excited. In other words, a ZZ gate may relate to the frequency of one qubit being dependent on the excitation or energization state of the other qubit, such that exciting one of the qubits can change the frequency of the other qubit. Symmetry may be broken with respect to a ZZ gate or ZZ interaction, where exciting a first qubit may change the frequency of a second qubit by a fixed amount, and exciting the second qubit in turn may change the frequency of the first qubit by the same fixed amount.

[0040] In some embodiments, a coupler component (e.g., a ZZ activated by a pulse (ZZAP) coupler) may be a facemon coupler component that may include three Josephson junctions (JJs), which may be structured, designed, and / or arranged in a quantum circuit such that a first JJ and a second JJ may be symmetric, or at least substantially symmetric, with respect to one another; due in part to the symmetry, or at least substantial symmetry, between the first JJ and the second JJ, the coupler component may be associated with a first mode of oscillation and a second mode of oscillation, and the third JJ may facilitate (e.g., enable or tolerate) a division (e.g., split) between the first mode and the second mode. For example, the symmetry between the first JJ and the second JJ may enable a mode of oscillation associated with a JJ of the coupler component to hybridize into two modes of oscillation (e.g., the first mode and the second mode). The first mode may be an even mode and the second mode may be an odd mode (or vice versa), which may provide coupling of opposite signs (e.g., positive and negative signs of coupling, respectively) between the first qubit and the second qubit (or between the first electronic element or component and the second electronic element or component, if the coupler component is located between and associated with (e.g., connected to) the first electronic element or component). The splitting between the first and second modes may be set, selected, adjusted, or determined based on a parameter associated with the third JJ (e.g., critical current, inductance, impedance, resistance, or other parameter).

[0041] The activation status of a ZZ gate (e.g., a ZZAP gate) associated with the coupler component and qubit, and thereby the coupling between the first qubit and the second qubit, can be controlled based on the excitation status of the first mode and the relationship between the first mode and the second mode (e.g., the first mode and the second mode can provide opposite signs of coupling). The excitation status can be based on whether a pulse (e.g., a radio frequency (RF) or π-type pulse) is applied to the coupler component. When no pulse is applied to the coupler component, the first mode can be in a ground state, and as a result, the ZZ gate can be in an inactive state, and there can be no coupling between the first qubit and the second qubit. This may be because when no pulse is applied, the first mode and the second mode may both be in a ground state, and due in part to the symmetry between the first mode and the second mode and the opposite signs of the coupling associated with the first mode and the second mode, the second mode may interfere with the first mode and cancel or suppress (e.g., squelch) the coupling between the first qubit and the second qubit. When a pulse (e.g., a pulse at a first frequency associated with the first mode) is applied to the coupler component (e.g., via a charge line in a quantum circuit), the first mode may be in an excited state, and as a result, the ZZ gate may be in an active state, and coupling may exist between the first qubit and the second qubit. In other embodiments, the activation status of the ZZ gate, and thereby the coupling between the first qubit and the second qubit, may be controlled based on whether the second mode is in an excited state relative to the ground state of the coupler component (e.g., based on applying a pulse at a second frequency associated with the second mode), rather than based on whether the first mode is in an excited state relative to the ground state of ground.

[0042] In some embodiments, the coupler component may be tunable, such that one or more parameters (e.g., frequency or other parameters) associated with the second JJ can be desirably tuned. For example, the coupler component may include a fourth JJ that may be in parallel with the second JJ and a wire component that may be in close proximity (e.g., within a defined distance) to the second JJ and the fourth JJ. The one or more parameters associated with the second JJ can be tuned (e.g., altered, adjusted, or changed) based on the current (e.g., amount of current) in the wire component and the proximity of the wire component to the second JJ and the fourth JJ (e.g., based on the amount of electromagnetic field provided to the second JJ and / or the fourth JJ).

[0043] In particular embodiments, the coupler component may be an L4ZZAP coupler component, which may comprise a JJ and a lambda (L) / 4 resonator arranged in parallel with each other in a quantum circuit, where the JJ may be associated with a first mode of oscillation and the L / 4 resonator may be associated with a second mode of oscillation. The first mode may be an even mode and the second mode may be an odd mode (or vice versa), thereby providing opposite signs of coupling between the first qubit and the second qubit.

[0044] The activation status of the ZZ gate associated with the coupler component and the qubit, and thereby the coupling between the first qubit and the second qubit, can be controlled based on the excitation status of the first mode and the relationship (e.g., inverse relationship) between the first mode and the second mode. The excitation status can be based on whether a pulse (e.g., an RF or π-type pulse) is applied to the coupler component. When no pulse is applied to the coupler component, the first mode can be in a ground state, and as a result, the ZZ gate can be in an inactive state, and there can be no coupling between the first qubit and the second qubit. This can be because when no pulse is applied, the first mode and the second mode can both be in a ground state, and due in part to the opposite signs of the coupling associated with the first mode and the second mode, the second mode associated with the L / 4 resonator can interfere with the first mode associated with the JJ, thereby canceling or suppressing the coupling between the first qubit and the second qubit. When a pulse (e.g., a pulse at a first frequency associated with a first mode) is applied to the coupler component (e.g., via a charge line in a quantum circuit), the first mode may be in an excited state, and as a result, the ZZ gate may be in an active state (e.g., a ZZ gate may be created), and coupling may exist between the first qubit and the second qubit. In other embodiments, the activation status of the ZZ gate, and thereby the coupling between the first qubit and the second qubit, may be controlled based not on whether the first mode is in an excited state relative to the ground ground state, but on whether the second mode is in an excited state and the relationship between the first and second modes with respect to the ground ground state (e.g., based on applying a pulse at a second frequency associated with the second mode).

[0045] In some embodiments, a coupler component (e.g., an L4ZZAP coupler component) may be tunable, such that one or more parameters associated with a JJ (e.g., frequency or other parameters) may be desirably tuned. For example, the coupler component may include a second JJ that may be in parallel with the JJ and a coil component that may be proximate to the JJ and the second JJ. The one or more parameters associated with the JJ may be tuned based on the current in the coil component and the proximity of the coil component to the JJ and the second JJ.

[0046] These and other aspects and embodiments of the disclosed subject matter will now be described with reference to the drawings.

[0047] 1 illustrates a block diagram of an example, non-limiting system 100 that may include a coupler component that can manage interaction or coupling between qubits in accordance with various aspects and embodiments of the disclosed subject matter. System 100 may include various components and circuits (e.g., quantum components and circuits) that may be arranged to perform one or more desired functions as described herein. System 100 may include, or be part of, a multi-qubit device or package that may have dimensions that may vary (e.g., an integrated circuit (IC) chip on which system 100 may reside may have dimensions), where the length of the device or package may range, for example, from the order of millimeters to tens of millimeters, the width of the device or package may range, for example, from the order of millimeters to tens of millimeters, and the thickness may range, for example, from approximately 1 millimeter (mm) to approximately 3 mm. It should be appreciated and understood that these dimensions of the device or package are exemplary, and that according to other embodiments, the device or package may have dimensions that differ (e.g., smaller or larger) than the example dimensions described herein.

[0048] In some embodiments, system 100 may include first qubit 102 and second qubit 104, which may be formed as part of a quantum circuit, which may be formed on a chip stack formed on a die (e.g., an IC chip). First qubit 102 and second qubit 104 may be part of a group of qubits of a quantum computer (e.g., a superconducting quantum computer). In particular embodiments, first qubit 102 and second qubit 104 may be transmon qubits, while in other embodiments, first qubit 102 and second qubit 104 may be different types of qubits. First qubit 102 and second qubit 104 may each include, for example, one or more Josephson junctions and shunt capacitors that may be associated with one or more Josephson junctions.

[0049] It may be desirable (e.g., wanted) to manage (e.g., control) the interaction or coupling between qubits (or between a first electronic element or component and a second electronic element or component), such as first qubit 102 and second qubit 104. According to various embodiments, system 100 may include a coupler component 106 that may enable and manage the interaction and coupling between first qubit 102 and second qubit 104. Coupler component 106 may be located between (e.g., logically or physically between) first qubit 102 and second qubit 104 in a quantum circuit. One end (e.g., a first port or lead) of coupler component 106 may be associated (e.g., connected) to first qubit 102, and another end (e.g., a second port or lead) of coupler component 106 may be associated (e.g., connected) to second qubit 104. Coupler component 106 may allow for inter-qubit interactions (e.g., interactions between first qubit 102 and second qubit 104) that may enable quantum logic gates. While some embodiments are described herein with respect to a coupler component between two qubits, it should be recognized and understood that, according to various other embodiments, the coupler component may be between or connected to a first electronic element or component (e.g., a quantum element or component) and a second electronic element or component of an electronic circuit (e.g., a quantum circuit) in which management of coupling between the first electronic element or component and the second electronic element or component is desired (e.g., desired).

[0050] According to various embodiments, the coupler component 106 may be a type of ZZAP coupler. In some embodiments, the coupler component 106 may be a facemon coupler component, which may be a multi-JJ coupler as described more fully herein. In other embodiments, the coupler component 106 may be an L4 ZZAP coupler, which may utilize JJ and L / 4 resonators as described more fully herein. In particular embodiments, the coupler component 106 may be a tunable coupler component, which may allow one or more parameters associated with the coupler component 106 (e.g., frequency, or another desired parameter) to be desirably tuned (e.g., altered, adjusted, or changed) as described more fully herein.

[0051] The coupler component 106 may comprise a first quantum component 108 (e.g., a first JJ) and a second quantum component 110 (e.g., a second JJ or an L / 4 resonator). In particular embodiments, the coupler component 106 may comprise other components as described herein (e.g., a third JJ, one or more capacitors, one or more inductors, or another type of component). The first quantum component 108 and the second quantum component 110 may be constructed, designed, and / or arranged in a quantum circuit with respect to each other such that multiple modes of oscillation may be created, which may include a first mode of oscillation 112 and a second mode of oscillation 114. First mode 112 may be an even mode and second mode 114 may be an odd mode (or vice versa), which may provide opposite signs of coupling between first qubit 102 and second qubit 104 (or between first electronic element or component and second electronic element or component). For example, first mode 112 may be associated with (e.g., provide) a first sign of coupling (e.g., a positive sign of coupling), and second mode 114 may be associated with a second sign of coupling (e.g., a negative sign of coupling) that may be the opposite of the first sign. In certain embodiments, first quantum component 108 (e.g., a first JJ) and second quantum component 110 (e.g., a second JJ) may be symmetric, or at least substantially symmetric, with respect to one another to facilitate creation of opposite modes (e.g., first mode 112 and second mode 114 may provide opposite signs of coupling).

[0052] Coupler component 106 may desirably (e.g., preferably, enhanced, or optimally) manage a gate, such as a ZZ gate, between first qubit 102 and second qubit 104 to facilitate desirably managing the interaction and coupling between first qubit 102 and second qubit 104. The ZZ gate (e.g., a ZZAP gate) may have an activation status that may include an inactive state (e.g., a closed gate) or an active status (e.g., an open gate). The activation status of the ZZ gate, and thereby the coupling between first qubit 102 and second qubit 104, may be controlled based on the excitation status of first mode 112 and the relationship between the first mode and second mode 114 (e.g., the opposite signs of the coupling associated with first mode 112 and second mode 114). The excitation status may be based on whether a pulse (e.g., an RF or π-type pulse) is applied to coupler component 106 via charge line 116, which may be located within or in close proximity (e.g., within a defined distance) to coupler component 106 in the quantum circuit. When no pulse is applied to coupler component 106, first mode 112 and second mode 114 may both be in their ground states, and as a result, the ZZ gate is in an inactive state and there may be no coupling between first qubit 102 and second qubit 104. This may be because when no pulse is applied to coupler component 106, first mode 112 and second mode 114 may both be in their ground states and, due in part to the relationship between first mode 112 and second mode 114, second mode 114 may interfere with first mode 112 and cancel or suppress (e.g., squelch or inhibit) the coupling between first qubit 102 and second qubit 104.When a pulse (e.g., an RF or π-type pulse at a first frequency associated with first mode 112) is applied to coupler component 106 via charge line 116 (e.g., by supplying a desired voltage or current to charge line 116), first mode 112 may be in an excited state, and as a result, the ZZ gate may be in an active state, and coupler component 106 may allow coupling to exist between first qubit 102 and second qubit 104. In other embodiments, the activation status of the ZZ gate, and thereby the coupling between first qubit 102 and second qubit 104, may be controlled not based on whether first mode 112 is in an excited state with respect to a ground ground state associated with coupler component 106, but based on whether second mode 114 is in an excited state with respect to a ground ground state associated with coupler component 106 (e.g., based on applying a pulse at a second frequency associated with second mode 114) and the relationship between first mode 112 and second mode 114.

[0053] This allows coupler component 106 to desirably (e.g., preferably, strengthen, or optimally) manage coupling between first qubit 102 and second qubit without requiring the use of flux-tuned gates and without requiring the use of microwave-activated gates with always-on coupling.

[0054] 2 and 3 illustrate diagrams of an example non-limiting system 200 that may utilize a multi-JJ configuration and may include coupler components (e.g., facemon coupler components) that may manage interaction or coupling between qubits, in accordance with various aspects and embodiments of the disclosed subject matter. FIG. 2 illustrates a schematic diagram of the non-limiting example system 200, and FIG. 3 illustrates a diagram (e.g., a quantum circuit layout diagram) of the non-limiting example system 200. The system may include various components and circuits (e.g., quantum components and circuits) that may be arranged to perform one or more desired functions as described herein. The system 200 may include a first qubit 202 and a second qubit 204. In some embodiments, the first qubit 202 and the second qubit 204 may be transmon qubits. In other embodiments, the first qubit 202 and the second qubit 204 may be different types of qubits.

[0055] According to various embodiments, system 200 may include a coupler component 206 that may enable and manage interaction and coupling between a first qubit 202 and a second qubit 204 (or between a first electronic element or component and a second electronic element or component in a circuit, when coupler component 206 is located between and associated with (e.g., connected to) the first electronic element or component and the second electronic element or component). Coupler component 206 may be located between (e.g., logically or physically between) first qubit 202 and second qubit 204 in a quantum circuit. One end (e.g., a first port or lead) of coupler component 206 may be associated with (e.g., connected to) the first qubit 202, and another end (e.g., a second port or lead) of coupler component 206 may be associated with (e.g., connected to) the second qubit 204.

[0056] In some embodiments, coupler component 206 may be a facemon coupler component that may comprise three JJs that may be structured, designed, and / or arranged in a quantum circuit such that first JJ 208 and second JJ 210 may be symmetric or at least substantially symmetric with respect to one another, and due in part to the symmetry or at least substantial symmetry between first JJ 208 and second JJ 210, coupler component 206 may be associated with a first mode of oscillation 212 and a second mode of oscillation 214, and third JJ 216 may facilitate (e.g., enable or allow) a splitting (e.g., a split) between first mode 212 and second mode 214, as described herein. In certain embodiments, instead of using third JJ 216, an inductor may be utilized to facilitate (e.g., enable or allow) a splitting between first mode 212 and second mode 214. The first mode 212 may be associated with a first frequency that may be on the order of gigahertz (GHz) (e.g., 5.5 GHz or other frequencies greater than or less than 5.5 GHz), and the second mode 214 may be associated with a second frequency that may also be on the order of gigahertz (e.g., 6.0 GHz or other frequencies greater than or less than 6.0 GHz) but different from the first frequency. In some embodiments, the first JJ 208, the second JJ 210, and / or the third JJ 216 may be fixed-frequency JJs, while in other embodiments, the first JJ 208, the second JJ 210, and / or the third JJ 216 may have adjustable (e.g., tunable) frequencies.

[0057] The first mode 212 may be an even mode and the second mode 214 may be an odd mode (or vice versa), which may provide opposite or different signs of coupling (e.g., positive and negative signs of coupling, respectively) between the first qubit 202 and the second qubit 204. In some embodiments, to promote symmetry and creation of opposite modes (e.g., first mode 212 and second mode 214 having opposite signs of coupling with respect to the first qubit 202 and the second qubit 204), the first JJ 208 and the second JJ 210 may be nominally or substantially identical to one another. For example, the capacitance, inductance, critical current, impedance, and / or resistance associated with the first JJ 208 and the second JJ 210 may be the same or substantially the same (e.g., when the coupler component 206 is in its ground state). During operation, the first JJ 208 and the second JJ 210 may act or behave like nonlinear inductors. As a result, when the first JJ 208 (or the second JJ 210) is driven at resonance, the first JJ 208 (or the second JJ 210) may acquire energy and become excited, where if it continues to be driven at resonance, it may de-excite and energy may leave the first JJ 208 (or the second JJ 210). This may be in contrast to a linear resonator, where if the linear resonator is driven at resonance, it may continue to acquire more energy. Symmetry, or at least substantial symmetry, between the first JJ 208 and the second JJ 210 may allow the coupler component 206 (e.g., the first JJ 208 and the second JJ 210 of the coupler component 206) to hybridize into two modes (e.g., a first mode 212 and a second mode 214 of oscillation, which may be opposite (e.g., an even mode and an odd mode)). As a result, the first mode 212 and the second mode 214 may balance each other, thereby canceling or at least substantially canceling (e.g., suppressing) the interaction or coupling between the first qubit 202 and the second qubit 204 when the first mode 212 and the second mode 214 are in their ground states.

[0058] The division between the first mode 212 and the second mode 214 may be set, selected, adjusted, or determined based on a parameter associated with the third JJ 216 (e.g., a critical current, an inductance, an impedance, a resistance, or other parameter), and different parameters of the third JJ 216 may result in a different division between the first mode 212 and the second mode 214 (e.g., may result in different respective frequencies or other respective parameters associated with the first mode 212 and the second mode 214). For example, based on parameters associated with the third JJ 216, the third JJ 216 may facilitate tuning, adjusting, or setting a first frequency associated with the first mode 212, a second frequency associated with the second mode 214, and / or the frequency space between the first mode 212 and the second mode 214 (e.g., may facilitate tuning, adjusting, or setting a separation between the first frequency associated with the first mode 212 and the second frequency associated with the second mode 214).

[0059] The quantum circuit may include several pads, including pad 218, pad 220, and pad 222. Pad 218, pad 220, and pad 222 may be formed of a desired conductive (e.g., superconducting) material. In the quantum circuit, each end (e.g., each lead or port) of the first JJ 208 may be associated (e.g., connected) to pad 218 and pad 222, and each end of the second JJ 210 may be associated (e.g., connected) to pad 220 and pad 222. Also, in the quantum circuit, an end of the third JJ 216 may be associated (e.g., connected) to pad 222 to connect the third JJ 216 to the first JJ 208 and the second JJ 210, and the other end of the third JJ 216 may be associated (e.g., connected) to ground 224 (e.g., the ground of the quantum circuit).

[0060] Coupler component 206 may desirably (e.g., preferably, enhanced, or optimally) manage a gate, such as a ZZ gate, between first qubit 202 and second qubit 204 to facilitate desirably managing the interaction and coupling between first qubit 202 and second qubit 204. Coupler component 206 may control the activation status of the ZZ gate (e.g., a ZZAP gate) to thereby control the interaction or coupling between first qubit 202 and second qubit 204 based on the excitation status of first mode 212 relative to the ground state of ground 224 and the relationship between first mode 212 and second mode 214 (e.g., opposite signs of coupling associated with first mode 212 and second mode 214). The excitation status may be based on whether a pulse (e.g., an RF or π-type pulse) is applied to coupler component 206 via charge line 226, which may be located within or proximate (e.g., within a defined distance) to coupler component 206 in the quantum circuit (e.g., located within or near the qubit pocket and proximate to third JJ 216 or another component). In some embodiments, excitation of first mode 212 and / or second mode 214 may be based on the collective excitation of first JJ 208, second JJ 210, and third JJ 216 in response to the application of a pulse to coupler component 206. Conversely, if no pulse is applied to coupler component 206, there may be a lack of excitation of first mode 212 and second mode 214 due to the collective lack of excitation of first JJ 208, second JJ 210, and third JJ 216 in response to the absence of a pulse.

[0061] When no pulse is applied to coupler component 206, first mode 212 may be in the ground state, and as a result, the ZZ gate may be in an inactive state, and there may be no, or at least little, coupling between first qubit 202 and second qubit 204. This is because, when no pulse is applied to coupler component 206 via charge line 226, first mode 212 and second mode 214 may both be in the ground state, and due in part to the symmetry, or at least substantial symmetry, of the first and second modes and the opposite signs of the coupling associated with first mode 212 and second mode 214, second mode 214 may interfere with first mode 212 and cancel, or at least substantially (and preferably or sufficiently) cancel, the coupling between first qubit 202 and second qubit 204.

[0062] When charging line 226 applies a pulse to coupler component 206 (e.g., an RF or π-type pulse at a first frequency associated with first mode 212) based on a desired voltage or current supplied to charging line 226, first mode 212 may be in an excited state, which may create an imbalance between first mode 212 and second mode 214, and as a result, coupler component 206 may control the ZZ gate to transition it from an inactive state to an active state, and as a result, there may be interaction or coupling between first qubit 202 and second qubit 204. Coupler component 206 may desirably be resonantly or non-adiabatically driven with an on-resonant pulse to activate ZZ interaction or coupling between first qubit 202 and second qubit 204. This may contrast with some existing couplers and techniques that require the use of off-resonant adiabatic driving to activate ZZ interaction or coupling between qubits. As a result of coupler component 206 being able to be resonantly or non-adiabatically driven with on-resonant pulses to activate ZZ interaction or coupling between first qubit 202 and second qubit 204, coupler component 206 may desirably be activated significantly more quickly for significantly faster gates compared to existing couplers and techniques. Coupler component 206 may also desirably control the interaction and coupling between first qubit 202 and second qubit 204 without requiring coupler component 206 to be always on, which may desirably reduce the amount of power utilized by coupler component 206 to manage the interaction and coupling between first qubit 202 and second qubit 204 (e.g., compared to existing couplers such as always-on couplers).Furthermore, because the coupler component 206 may be nonlinear, the coupler component 206 may desirably be driven with a π-type (e.g., a π, 2π, π / 2, π / 4, or other π-type pulse) or RF pulse, which may use a relatively low amount of power compared to existing couplers and may also enhance (e.g., improve, increase, or optimize) the efficiency of the coupler component 206.

[0063] It should be appreciated and understood that in other embodiments, the activation status of the ZZ gate, and thereby the coupling between the first qubit 202 and the second qubit 204, can be controlled not based on whether the first mode 212 is in an excited state with respect to the ground state of ground 224, but based on whether the second mode 214 is in an excited state with respect to the ground state of ground 224 and the relationship between the first mode 212 and the second mode 214 (e.g., based on applying a pulse at a second frequency associated with the second mode 214).

[0064] In particular embodiments, coupler component 206 may comprise a third mode of oscillation that may be associated with third JJ 216. If desired (e.g., desired), the activation status of the ZZ gate, and thereby the coupling between first qubit 202 and second qubit 204, may be controlled based on whether the third mode of oscillation is in an excited state. For example, the ZZ gate may be transitioned from an inactive state to an active state (e.g., the ZZ gate may be turned on) by exciting the third mode of oscillation, e.g., based on applying pulses to coupler component 206 at a third frequency associated with the third mode of oscillation. Note, however, that the speed of the ZZ gate associated with exciting first mode 212 or second mode 214 may typically be faster than the speed of the ZZ gate associated with exciting the third mode of oscillation.

[0065] In some embodiments, coupler component 206 may be structured to be associated with one or more frequencies above the frequencies associated with first qubit 202 and second qubit 204. In other embodiments, coupler component 206 may be structured to be associated with one or more frequencies below the frequencies associated with first qubit 202 and second qubit 204.

[0066] In particular embodiments, system 200 may include other components including capacitor (C) 228, capacitor 230, capacitor 232, capacitor 234, capacitor 236, capacitor 238, capacitor 240, and / or capacitor 242, which may be arranged in a quantum circuit such as that illustrated in FIG. 2 . Capacitor 228 may be connected in parallel to first JJ 208, with each end of capacitor 228 connected to pad 218 and pad 222. Capacitor 230 may be connected in parallel to second JJ 210, with each end of capacitor 230 connected to pad 220 and pad 222. Capacitor 232 may be connected in parallel to third JJ 216, with each end of capacitor 232 connected to pad 222 and ground 224. Capacitor 234 may have one end (e.g., a lead or plate) connected to first JJ 208, with the other end of capacitor 234 connected to ground 224. Capacitor 236 may have one end (e.g., a lead or plate) connected to second JJ 210, and the other end of capacitor 236 may be connected to ground 224. Capacitor 238 may have one end (e.g., a lead or plate) connected to pad 218 (and other components connected to pad 218), and the other end of capacitor 238 may be connected to pad 220 (and other components connected to pad 220). In some embodiments, capacitor 240 (e.g., a capacitive coupler) may (e.g., optionally) be positioned between and connected to pad 218 and first qubit 202 at each end of capacitor 240, and capacitor 242 (e.g., a capacitive coupler) may (e.g., optionally) be positioned between and connected to pad 220 and second qubit 204 at each end of capacitor 242.

[0067] 4 shows a block diagram of an example non-limiting system 400 that may utilize a multi-Josephson junction configuration and may include a tunable coupler component (e.g., a tunable facemon coupler component) that may manage the interaction or coupling between qubits in accordance with various aspects and embodiments of the disclosed subject matter. System 400 may include a first qubit 402 and a second qubit 404. In some embodiments, first qubit 402 and second qubit 404 may be transmon qubits, or in other embodiments, first qubit 402 and second qubit 404 may be different types of qubits.

[0068] According to various embodiments, system 400 may include a coupler component 406 that may enable and manage interaction and coupling between a first qubit 402 and a second qubit 404 (or between a first electronic element or component and a second electronic element or component in a circuit, when coupler component 406 is located between and associated with (e.g., connected to) the first electronic element or component and the second electronic element or component). Coupler component 406 may be located between (e.g., logically or physically between) first qubit 402 and second qubit 404 in a quantum circuit. One end (e.g., a first port or lead) of coupler component 406 may be associated with (e.g., connected to) the first qubit 402, and another end (e.g., a second port or lead) of coupler component 406 may be associated with (e.g., connected to) the second qubit 404.

[0069] In some embodiments, coupler component 406 may be a tunable facemon coupler component that may comprise four JJs that may be arranged in a quantum circuit such that first JJ 408 and second JJ 410 may be symmetric, or at least substantially symmetric, with respect to one another; due in part to such symmetry, coupler component 406 may be associated with a first mode of oscillation 412 and a second mode of oscillation 414; and third JJ 416 may facilitate splitting between first mode 412 and second mode 414 as described herein. First mode 412 may be an even mode and second mode 414 may be an odd mode (or vice versa), which may provide opposite or different signs of coupling between first qubit 402 and second qubit 404. In some embodiments, the first JJ 408 and the second JJ 410 may be nominally or substantially identical to one another, which may allow for such symmetry between the first JJ 408 and the second JJ 410. In particular embodiments, the system 400 may include a fourth JJ 418 that may be connected in parallel to the second JJ 410 to facilitate tunability of the coupler component 406 as described herein.

[0070] System 400 may also include a charging line 420, which may be located within or in close proximity (e.g., within a defined distance) to coupler component 406 in the quantum circuit. Pulses (e.g., RF or π-type pulses) may be selectively applied to coupler component 406 via charging line 420 to facilitate control of the excitation state of first mode 412 (or the excitation state of second mode 414) to facilitate control of the activation state of a ZZ gate associated with coupler component 406, which may facilitate control of the interaction or coupling between first qubit 402 and second qubit 404, as described herein. Coupler component 406 may operate in the same or similar manner as coupler component 206, e.g., of FIGS. 2 and 3 and described herein, except that coupler component 406 may be tunable, as described more fully herein.

[0071] The quantum circuit of system 400 may also include several pads, including pad 422, pad 424, and pad 426. Pad 422, pad 424, and pad 426 may be formed of a desired conductive (e.g., superconducting) material. In the quantum circuit, each end (e.g., each lead or port) of the first JJ 408 may be associated (e.g., connected) to pad 422 and pad 426, and each end of the second JJ 410 may be associated (e.g., connected) to pad 424 and pad 426. Also, in the quantum circuit, an end of the third JJ 416 may be associated (e.g., connected) to pad 426 to connect the third JJ 416 to the first JJ 408 and the second JJ 410, and the other end of the third JJ 416 may be associated with ground 428. In some embodiments, the quantum circuit of system 400 may include (e.g., optionally include) a capacitor that can act as a capacitive coupler, and pad 430 may be or be associated with a capacitor that can act as a capacitive coupler for coupling first qubit 402 to coupler component 406, and pad 432 may be or be associated with a capacitor that can act as a capacitive coupler for coupling second qubit 404 to coupler component 406.

[0072] In particular embodiments, to facilitate enabling the coupler component 406 to be desirably tuned, the quantum circuit of the system 400 may also include a coil component (COIL COMP) 434 that may be formed or located in proximity (e.g., within a defined distance) to the second JJ 410 and the fourth JJ 418. The coil component 434 may include a wire component (e.g., a superconducting wire) that may include a desired number of helices (e.g., one helix or multiple helices) or may be a coil having a single helix. When it is desired to tune the second JJ 410, a desired current may be supplied to the coil component 434, and the current in the coil component 434 may generate (e.g., create) a magnetic flux. The amount of magnetic flux generated may be based on the amount of current in the coil component 434 (e.g., the amount of current sent through the coil or wire of the coil component 434), and the amount of magnetic flux applied to the second JJ 410 and the fourth JJ 418 may be based on the amount of magnetic flux generated by the coil component 434 and the proximity of the coil component 434 to the second JJ 410 and the fourth JJ 418. Due in part to the fourth JJ 418 connected in parallel to the second JJ 410 and the proximity of the coil component 434 to the second JJ 410 and the fourth JJ 418, one or more parameters associated with the second JJ 410 (e.g., frequency or another parameter) may be tuned (e.g., altered, adjusted, or changed lower or higher) based on the magnetic flux generated by the coil component 434.

[0073] Coupler component 406 may be tuned for several reasons. For example, during fabrication of coupler component 406, first JJ 408 and second JJ 410 may potentially not be sufficiently identical to one another, which may result in first mode 412 and second mode 414 not being sufficiently opposed to one another to sufficiently cancel the interaction or coupling between first qubit 402 and second qubit 404 when coupler component 406 is in the ground state. In such a case, one or more parameters associated with the second JJ 410, such as the frequency, may be desirably tuned (e.g., adjusted) to enable the second JJ 410 to be identical to, or at least substantially and sufficiently close to, the first JJ 408 when the coupler component 406 is in its ground state, so that the first mode 412 and the second mode 414 are sufficiently opposed to each other and sufficiently cancel or suppress any interaction or coupling between the first qubit 402 and the second qubit 404.

[0074] As another example of the use of tunable coupler component 406, coupler component 406 may be utilized to facilitate creation of a flux gate (e.g., a flux ZZ gate), where the frequency of the second JJ 410 may be tuned to a different frequency based on a current supplied to coil component 434 to facilitate tuning the frequency of the second JJ 410 to a different frequency to facilitate placing the second mode 414 out of balance with the first mode 412. Adjusting the frequency associated with the second JJ 410 and / or the second mode 414 to facilitate placing the second mode 414 out of balance with the first mode 412 may result in a transition of the ZZ gate from an inactive state to an activated state, and a desired interaction or coupling between the first qubit 402 and the second qubit 404 may occur.

[0075] Turning briefly to Figure 5, Figure 5 presents an illustration of an example graph 500 of a simulation of a facemon coupler component where the frequency associated with the facemon coupler component exceeds the frequency associated with the qubits (e.g., a first qubit and a second qubit) in accordance with various aspects and embodiments of the disclosed subject matter. Graph 500 presents respective data points for respective parameters, including ZZ coupling of a ZZ gate, associated with the facemon coupler component, at a rate of coupling of a system of two qubits at the facemon coupler component (e.g., at a detuning of 50 megahertz (MHz)), where the frequency associated with the facemon coupler component may exceed the frequency associated with the two qubits in frequency space. Graph 500 includes data points 502, which may represent ZZ interaction or coupling between two qubits when the facemon coupler component is in a ground state, data points 504, which may represent ZZ interaction or coupling between two qubits when a first mode (mode A) of oscillation of the facemon coupler component is in an excited state, and data points 506, which may represent ZZ interaction or coupling between two qubits when a second mode (mode B) of oscillation of the facemon coupler component is in an excited state. Graph 500 also includes data points 508, which may represent anharmonicity associated with the facemon coupler component when the first mode (mode A) of the facemon coupler component is in an excited state, and data points 510, which may represent anharmonicity associated with the facemon coupler component when the second mode (mode B) of the facemon coupler component is in an excited state.

[0076] As can be observed in graph 500 for data point 502 of the simulation results of ZZ coupling of a ZZ gate, when the facemon coupler component is in the ground state, there can be a region of zero coupling, or low ZZ coupling of effective or approximately zero coupling, at approximately 5.5 gigahertz (GHz), as shown by reference numeral 512 on graph 500. Also, as can be observed in graph 500 for data point 502, when one of the modes (e.g., the first mode of oscillation or the second mode of oscillation) of the facemon coupler component is in an excited state (e.g., with respect to the ground ground state), the ZZ coupling of the ZZ gate can be enhanced (e.g., increased), achieving several MHz for gates of less than 100 nanoseconds (ns), as shown by reference numerals 504 and 506 on graph 500.

[0077] Furthermore, data points 508 and 510, which respectively represent the anharmonicity simulation results for the two modes, may indicate that the facemon coupler component can desirably be driven resonantly with the facemon coupler component being able to return to its ground state. The facemon coupler component can essentially act similarly to a qubit, and because the facemon coupler component can be a nonlinear coupler, the facemon coupler component can desirably be turned on and off by driving it resonantly.

[0078] Referring briefly to Figure 6, Figure 6 illustrates a diagram of an example graph 600 of a simulation of a facemon coupler component where the frequency associated with the facemon coupler component is below the frequency associated with the qubits (e.g., a first qubit and a second qubit), in accordance with various aspects and embodiments of the disclosed subject matter. Graph 600 presents respective data points for respective parameters, including ZZ coupling of a ZZ gate, associated with the facemon coupler component, at a rate of coupling of a system of two qubits at the facemon coupler component (e.g., at a detuning of 50 megahertz (MHz)), where the frequency associated with the facemon coupler component may be below the frequency associated with the two qubits in frequency space. Graph 600 includes data point 602, which may represent ZZ interaction or coupling between two qubits when the facemon coupler component is in a ground state, data point 604, which may represent ZZ interaction or coupling between two qubits when a first mode (mode A) of oscillation of the facemon coupler component is in an excited state, and data point 606, which may represent ZZ interaction or coupling between two qubits when a second mode (mode B) of oscillation of the facemon coupler component is in an excited state. Graph 600 also includes data point 608, which may represent an anharmonicity associated with the facemon coupler component when the first mode (mode A) of the facemon coupler component is in an excited state, and data point 610, which may represent an anharmonicity associated with the facemon coupler component when the second mode (mode B) of the facemon coupler component is in an excited state.

[0079] As can be observed in graph 600 for data point 602 relating to the simulation results of ZZ coupling of the ZZ gate, when the facemon coupler component is in the ground state, there can be a wide region of low ZZ coupling, as indicated by reference numeral 612 on graph 600. Also, as can be observed in graph 600 for data points 604 and 606, when one of the modes of the facemon coupler component (e.g., the first mode of oscillation (mode A) or the second mode of oscillation (mode B)) is in an excited state (e.g., with respect to the ground ground state), the ZZ coupling of the ZZ gate can be enhanced (e.g., increased) and can reach approximately 10 MHz, while the facemon coupler component can maintain idle ZZ coupling at approximately 1 kilohertz (kHz), as indicated by reference numeral 604 on graph 600.

[0080] Graph 600 may also comprise 2chi-related data points 614, which may each comprise 2chiAq2, which may represent the shift in frequency of the second qubit when a first mode (mode A) of the facemon coupler component is excited, 2chiBq2, which may represent the shift in frequency of the second qubit when a second mode (mode B) of the facemon coupler component is excited, 2chiAq1, which may represent the shift in frequency of the first qubit when a first mode (mode A) of the facemon coupler component is excited, and 2chiBq1, which may represent the shift in frequency of the first qubit when a second mode (mode B) of the facemon coupler component is excited. As can be observed in graph 600 for (e.g., compared to) each data point 614 associated with 2chi (e.g., 2chiAq2, 2chiBq2, 2chiAq1, and 2chiBq1), and for data point 602 (e.g., ZZ coupling when the facemon coupler component is in the ground state), the ZZ / 2chi ratio appears to be relatively improved for frequencies associated with the coupler component that are below the frequency associated with the qubit, compared to when the frequency associated with the coupler component is above the frequency associated with the qubit. This may allow for a more desirable (e.g., better) unrefocused gate associated with the qubit.

[0081] 7 and 8 illustrate diagrams of an example non-limiting system 700 that may utilize a JJ and resonator configuration and may include a coupler component (e.g., an L4ZZAP coupler component) that may manage interaction or coupling between qubits, in accordance with various aspects and embodiments of the disclosed subject matter. FIG. 7 shows a schematic diagram of the non-limiting example system 700, and FIG. 8 shows a diagram (e.g., a quantum circuit layout diagram) of the non-limiting example system 700. The system may include various components and circuits (e.g., quantum components and circuits) that may be arranged to perform one or more desired functions as described herein. The system 700 may include a first qubit 702 and a second qubit 704. In some embodiments, the first qubit 702 and the second qubit 704 may be transmon qubits. In other embodiments, the first qubit 702 and the second qubit 704 may be different types of qubits.

[0082] According to various embodiments, system 700 may include a coupler component 706 that may enable and manage interaction and coupling between a first qubit 702 and a second qubit 704. The coupler component 706 may be located in a quantum circuit between (e.g., logically or physically between) the first qubit 702 and the second qubit 704. One end (e.g., a first port or lead) of the coupler component 706 may be associated with (e.g., connected to) the first qubit 702, and another end (e.g., a second port or lead) of the coupler component 706 may be associated with (e.g., connected to) the second qubit 704.

[0083] In some embodiments, coupler component 706 may be an L4ZZAP coupler component that may comprise a JJ 708 and an L / 4 resonator 710 that may be placed in parallel with each other in a quantum circuit, where the JJ 708 may be associated with a first mode of oscillation 712 and the L / 4 resonator 710 may be associated with a second mode of oscillation 714. The first mode 712 may be an even mode and the second mode 714 may be an odd mode (or vice versa), which may provide opposite signs of coupling between the first qubit 702 and the second qubit 704.

[0084] Coupler component 706 can control the activation status of ZZ gates associated with coupler component 706 and qubits 702 and 704, and thereby the coupling between first qubit 702 and second qubit 704, based on the excitation status of first mode 712 and the relationship between first mode 712 and second mode 714. The excitation status may be based on whether a pulse (e.g., an RF or π-type pulse) is applied to coupler component 706 via charge line 716, which may be located within or in close proximity (e.g., within a defined distance) to coupler component 706 in the quantum circuit (e.g., located within or near the qubit pocket and in close proximity to JJ 708 or another component). When no pulse is applied to coupler component 706, first mode 712 may be in the ground state, and as a result, the ZZ gate may be in an inactive state, and there may be no, or at least little, coupling between first qubit 702 and second qubit 704. This is because when no pulse is applied to coupler component 706 and first mode 712 and second mode 714 may both be in the ground state, due in part to the symmetry between first mode 712 and second mode 714 and the opposite signs of the coupling associated with first mode 712 and second mode 714, second mode 714 associated with L / 4 resonator 710 may interfere with first mode 712 associated with JJ 708 and may cancel, or at least substantially (and preferably or sufficiently) cancel or suppress, the coupling between first qubit 702 and second qubit 704. When the charging line 716 applies a pulse (e.g., an RF or π pulse at a first frequency associated with the first mode 712) to the coupler component 706 based on a desired voltage or current supplied to the charging line 716, the first mode 712 may be in an excited state, which may create an imbalance between the first mode 712 and the second mode 714, and as a result, the coupler component 706 may control the ZZ gate to transition the ZZ gate from an inactive state to an active state, which may result in coupling between the first qubit 702 and the second qubit 704. Thus, the coupler component 706 can desirably control the interaction and coupling between the first qubit 702 and the second qubit 704 without requiring the coupler component 706 to be always on, which may desirably reduce the amount of power utilized by the coupler component 706 to manage the interaction and coupling between the first qubit 702 and the second qubit 704 (e.g., compared to existing couplers such as always-on couplers).

[0085] Further, with respect to first qubit 702, second qubit 704, coupler component 706, and other components of system 700, first qubit 702 may include a JJ 718 and a capacitor 720, which may be connected in parallel to each other. First qubit 702 may also include a capacitor 722 and a capacitor 724, which may each be connected to a JJ 718 and a capacitor 720 at one end and to ground 726 at the other end. Similarly, second qubit 704 may include a JJ 728 and a capacitor 730, which may be connected in parallel to each other. Second qubit 704 may also include a capacitor 732 and a capacitor 734, which may each be connected to a JJ 728 and a capacitor 730 at one end and to ground 726 at the other end.

[0086] Further with respect to JJ 708, capacitor 736 may be connected in parallel to JJ 708. At one end (e.g., a lead or connector) of JJ 708 and capacitor 736, capacitor 738 and capacitor 740 may be connected to JJ 708 and capacitor 736, with capacitor 740 connected to ground 726 at its other end. At the other end of JJ 708 and capacitor 736, capacitor 742 and capacitor 744 may be connected to JJ 708 and capacitor 736, with capacitor 744 connected to ground 726 at its other end.

[0087] The L / 4 resonator 710 may include an inductor (I) 746, which may be connected in parallel with the JJ 708 of the coupler component 706. As shown in FIG. 7, one end of the inductor 746 may also be connected to the capacitors 738 and 740, and the other end of the inductor 746 may be connected to the capacitors 742 and 744. The L / 4 resonator 710 may also include capacitors 748 and 750, which may be connected at one end (e.g., a lead or connector) to the capacitors 738 and 742, respectively, and at their other ends to ground 726, as shown in FIG.

[0088] In some embodiments, system 700 may include (e.g., optionally include) a capacitor 752 (e.g., a capacitive coupler) that may be coupled between and connected to the first qubit 702 and coupler component 706 (e.g., capacitor 738 of coupler component 706) to facilitate coupling of the first qubit 702 to coupler component 706. System 700 may also include (e.g., optionally include) a capacitor 754 that may be coupled between and connected to the second qubit 704 and coupler component 706 (e.g., capacitor 742 of coupler component 706) to facilitate coupling of the second qubit 704 to coupler component 706.

[0089] As illustrated in the example quantum circuit layout of FIG. 8, the quantum circuit layout may include various pads, including pads that may correspond to capacitors 748 and 750, pads that correspond to capacitors 752 and 754, and pads 756 and 758, where capacitor 740 may be associated with pad 756 and capacitor 744 may be associated with pad 758.

[0090] 9 shows a block diagram of one example of a non-limiting system 900 that may utilize a JJ and resonator configuration and may include a tunable coupler component (e.g., an L4ZZAP coupler component) that may manage the interaction or coupling between qubits in accordance with various aspects and embodiments of the disclosed subject matter. System 900 may include a first qubit 902 and a second qubit 904. In some embodiments, first qubit 902 and second qubit 904 may be transmon qubits, or in other embodiments, first qubit 902 and second qubit 904 may be different types of qubits.

[0091] According to various embodiments, system 900 may comprise a coupler component 906 that may enable and manage interaction and coupling between first qubit 902 and second qubit 904. Coupler component 906 may be located between (e.g., logically or physically between) and connected to first qubit 902 and second qubit 904 in a quantum circuit. In some embodiments, coupler component 906 may be an L4ZZAP coupler component that may comprise a JJ 908 and an L / 4 resonator 910 that may be positioned in parallel with each other in the quantum circuit, where JJ 908 may be associated with a first mode of oscillation 912 and L / 4 resonator 910 may be associated with a second mode of oscillation 914. The first mode 912 may be an even mode and the second mode 914 may be an odd mode (or vice versa), which may provide opposite signs of coupling between the first qubit 902 and the second qubit 904 as described herein.

[0092] Coupler component 906 can desirably control the activation status of ZZ gates associated with coupler component 906 and qubits 902 and 904, and thereby the coupling between first qubit 902 and second qubit 904, based on the excitation status of first mode 912 relative to second mode 914, as described herein. The excitation status may be based on whether a pulse (e.g., an RF or π-type pulse) is applied to coupler component 906 via charge line 916, which may be located within or proximate (e.g., within a defined distance) to coupler component 906 in the quantum circuit (e.g., located within or near the qubit pocket and proximate to JJ 908 or another component). Coupler component 906 may operate in the same or similar manner as coupler component 706, e.g., of FIGS. 7 and 8 and described herein, except that coupler component 906 may be tunable, as described more fully herein.

[0093] In some embodiments, to facilitate enabling the coupler component 906 to be desirably tuned, the quantum circuit of the system 900 may also include a second JJ 918 and a coil component 920. The second JJ 918 may be connected in parallel to the JJ 908 (e.g., a split Josephson junction). The coil component 920 may be formed or located in close proximity (e.g., within a defined distance) to the JJ 908 and the second JJ 918. The coil component 920 may include a wire component (e.g., a superconducting wire) that may include a desired number of helices (e.g., one helix or multiple helices) or may be a coil having a single helix. When it is desired to tune the JJ 908, a desired current may be supplied to the coil component 920, and the current in the coil component 920 may generate (e.g., create) a magnetic flux. The amount of magnetic flux generated may be based on the amount of current in the coil component 920, and the amount of magnetic flux applied to the JJ 908 and the second JJ 918 may be based on the amount of magnetic flux generated and the proximity of the coil component 920 to the JJ 908 and the second JJ 918. Due in part to the second JJ 918 being connected in parallel to the JJ 908 and the proximity of the coil component 920 to the JJ 908 and the second JJ 918, one or more parameters associated with the JJ 908 (e.g., frequency or another parameter) may be desirably tuned (e.g., altered, adjusted, or changed lower or higher) based on the magnetic flux generated by the coil component 920.

[0094] In some embodiments, if, from fabrication of the quantum device, a first mode 912 associated with the JJ 908 is not sufficiently opposed to a second mode 914 associated with the L / 4 resonator 910, the coil component 920 and the current supplied thereto may desirably tune (e.g., adjust) one or more parameters associated with the coupler component 906, such as a frequency (e.g., a frequency of the JJ 908 of the coupler component 906), to, for example, position the second mode 914 sufficiently opposed to the first mode 912. In certain embodiments, the coil component 920 and the current supplied thereto may desirably tune one or more parameters associated with the coupler component 906, such as a frequency, to facilitate positioning the first mode 912 unbalanced from the second mode 914. For example, adjusting the frequency associated with the first mode 412 to be unbalanced with the second mode 414 may result in a transition of the ZZ gate from an inactive state to an activated state, and may result in a desired interaction or coupling between the first qubit 902 and the second qubit 904.

[0095] The quantum circuit of system 900 may also include several pads, including pad 922, pad 924, pad 926, pad 928, pad 930, and pad 932. Pads 922-932 may be formed of a desired conductive (e.g., superconducting) material. In the quantum circuit, each end (e.g., a lead or port) of JJ 908 (and second JJ 918) may be associated (e.g., connected) with pad 922 and pad 924. Also in the quantum circuit, resonator 910 may include an inductor and a capacitor, as described herein. A capacitor of resonator 910 may be or be associated with pad 926, and another capacitor of resonator 910 may be or be associated with pad 928. Pads 926 and 928 of resonator 910 and the associated capacitors may be connected to ground 934. In some embodiments, the quantum circuit of system 900 may include (e.g., optionally include) a capacitor that can act as a capacitive coupler, and pad 930 may be or be associated with a capacitor that can act as a capacitive coupler for coupling first qubit 902 to coupler component 906, and pad 932 may be or be associated with a capacitor that can act as a capacitive coupler for coupling second qubit 904 to coupler component 906.

[0096] Coupler components as described herein may have several advantages over existing coupler technology. For example, the disclosed coupler components may desirably (e.g., preferably, enhanced, or optimally) have enhanced performance and efficiency relative to existing couplers and may provide enhanced management of interaction and coupling between qubits. The disclosed coupler components may desirably activate more quickly and have faster gates compared to existing couplers. The disclosed coupler components may also utilize less power than existing couplers (e.g., existing always-on couplers). The disclosed coupler components may further desirably manage interaction and coupling between qubits without requiring detuning.

[0097] Although the quantum devices described herein illustrate only two qubits and one coupler component that may be formed on a single die, it should be recognized and understood that in some embodiments, a quantum device may include any desired number of qubits (e.g., more than two qubits) and any desired number of coupler components (e.g., one or more coupler components) each associated with the qubits, that may be formed on a chip stack on a single die.

[0098] Turning briefly to FIG. 10 , FIG. 10 presents an illustration of an exemplary graph 1000 of a simulation of the ground state coupling of a coupler component (e.g., an L4ZZAP coupler component) that may utilize a JJ and resonator (e.g., an L / 4 resonator) configuration in accordance with various aspects and embodiments of the disclosed subject matter. Graph 1000 presents respective data points (along the y-axis) of inter-qubit coupling related to (e.g., as a function of) frequency (along the x-axis). As can be observed in graph 1000 with respect to data points 1002 related to simulation results of the ground state coupling of a coupler component connected to and positioned between a pair of qubits, when the coupler component is in the ground state, the inter-qubit coupling (e.g., approximately 4 GHz to 5 GHz) may be desirably (e.g., preferably, favorably, or optimally) low, or even have zero coupling, or at least near-zero coupling, in the qubit frequency band of the qubits. This may be because the coupling qubit (e.g., a qubit formed using a JJ in a JJ and resonator configuration) and the L / 4 resonator may have coupling of opposite signs (e.g., may be associated with opposite modes), and when the coupler component is in the ground state, a first mode associated with the coupling qubit and a second mode associated with the L / 4 resonator may interfere with each other due to broadband cancellation of the qubit's coupling. Also, as can be observed in graph 1000 for data point 1002, there may be peaks at approximately 5.5 GHz and 6 GHz (e.g., peak 1004 and peak 1006) at data point 1002, which may be associated with a first mode of oscillation and a second mode of oscillation of the coupler component, respectively.

[0099] 11, which illustrates a diagram of an example graph 1100 of a simulation of gate speed (e.g., ZZ gate speed) of a coupler component (e.g., an L4ZZAP coupler component) that may utilize a JJ and resonator (e.g., an L / 4 resonator) configuration in accordance with various aspects and embodiments of the disclosed subject matter. Graph 1100 presents respective data points for respective parameters, including gate speed at the frequency of a gate (e.g., a ZZ gate) associated with the coupler component, related to (e.g., as a function of) the frequency (along the x-axis) of a pulse applied to the coupler component.

[0100] As can be observed in graph 1100 for data point 1102 related to simulation results related to a gate associated with the coupler component, by placing the L / 4 mode relatively close to the frequency of a coupling qubit (e.g., a qubit formed using a JJ in a JJ and resonator configuration), zero, or at least near-zero, coupling between the qubits due to cancellation between the first and second modes when the coupler component is in its ground state can be confirmed by Cauer code simulation of the combined system. Data point 1102 can represent a ZZ gate between two qubits when the L4 ZZAP coupler component is in its ground state. At data point 1102 in graph 1100, the zero in the ZZ gate between the two qubits is shown at approximately 5.0 GHz, as indicated by reference numeral 1104. The ZZ rate can reach approximately 10 MHz when the coupler component is activated by exciting one of the two modes, while the ZZ can remain below 10 kHz when the coupler component is in its ground state.

[0101] 12 illustrates a block diagram of an exemplary system 1200 that may be utilized to create, form, or design a device including qubits, coupler components, and / or other quantum components, elements, or circuits in accordance with various aspects and embodiments of the disclosed subject matter. System 1200 may comprise a processor component 1202 and a data store 1204. According to various embodiments, processor component 1202 may comprise or be associated with (e.g., communicatively connected to) device formation components 1206 that may be utilized to create, form, or design various components, including qubits, coupler components, and associated quantum components, elements, or circuits, of or associated with device 1208, as described more fully herein. For example, device formation components 1206 may be utilized to create, form, or design various components of device 1208, which may be formed on or located on chip 1210 (e.g., a quantum computer or qubit device IC chip), or more than one chip, if desired. The various components may include, for example, qubit 1212, coupler component 1214, JJ 1216, capacitor 1218, resonator 1220, inductor 1222, and / or associated circuitry 1224.

[0102] As part of, and to facilitate, the creation, formation, or design of, or various components associated with, device 1208, device formation components 1206 may form or process substrates. As part of, or to facilitate the creation, formation, or design of, or various components and / or circuits associated with, device 1208, device formation components 1206 may also form, deposit, remove (e.g., selectively remove or etch), pattern, or process materials, including silicon or silicon-based materials (e.g., dielectric materials), superconducting materials, or other materials, of device 1208. For example, device formation components 1206 may utilize and / or control various processes including fabrication processes, miniaturization processes, nano-fabrication processes, material deposition processes (e.g., low pressure chemical vapor deposition (LPCVD) processes), masking or photoresist processes, photolithography processes, chemical etching processes (e.g., reactive-ion etching (RIE) processes, potassium hydroxide (KOH) etching processes), other etching or removal processes, epitaxial processes, material filtration processes, patterning processes, planarization processes (e.g., chemical-mechanical planarization (CMP) processes), component formation processes, and / or other desired processes to desirably form, deposit, remove (e.g., selectively remove or etch), pattern, or treat material to facilitate the creation or formation of respective components or circuits of device 1208.

[0103] Processor component 1202 may operate in conjunction with other components (e.g., data store 1204, device formation component 1206, or another component) to facilitate the performance of various functions of system 1200. Processor component 1202 may utilize one or more processors, microprocessors, or controllers that may process data such as information regarding the design, creation, or formation of quantum computers, qubits 1212, coupler components 1214, JJs 1216, capacitors 1218, resonators 1220 (e.g., microwave resonators), inductors 1222, waveguides, electrodes, filters, and / or other components or devices, as well as information regarding circuit design criteria, circuit design algorithms, traffic flow, policies, protocols, interfaces, tools, and / or other information, to facilitate operation of system 1200 as more fully disclosed herein and to control the flow of data between system 1200 and other components (e.g., computer components, computers, laptop computers, other computing or communication devices, or network devices) associated with (e.g., connected to) system 1200.

[0104] Data store 1204 may store data structures (e.g., user data, metadata), code structures (e.g., modules, objects, hashes, classes, procedures), or instructions, information regarding the design, creation, or formation of quantum computers, qubits 1212, coupler components 1214, JJs 1216, capacitors 1218, resonators 1220 (e.g., microwave resonators), inductors 1222, waveguides, electrodes, filters, and / or other components or devices, and information regarding circuit design criteria, circuit design algorithms, traffic flows, policies, protocols, interfaces, tools, and / or other information to facilitate control of operations associated with system 1200. In an aspect, processor component 1202 may be operatively coupled to data store 1204 (e.g., through a memory bus) for storing and retrieving information desired to operate and / or provide functionality to, at least in part, data store 1204, device formation component 1206, or other components, and / or virtually any other operational aspect of system 1200.

[0105] It should be appreciated that the data store 504 as described herein may include volatile and / or non-volatile memory. By way of example, and not limitation, non-volatile memory may include read-only memory (ROM), programmable ROM (PROM), electrically programmable ROM (EPROM), electrically erasable ROM (EEPROM), or flash memory. Volatile memory may include random access memory (RAM), which may act as external cache memory. By way of example, and not limitation, RAM may be available in many forms, including synchronous RAM (SRAM), dynamic RAM (DRAM), synchronous DRAM (SDRAM), double data rate SDRAM (DDR SDRAM), enhanced SDRAM (ESDRAM), Synchlink DRAM (SLDRAM), and direct Rambus RAM (DRRAM). The memory of the disclosed aspects is intended to include, but is not limited to, these and other suitable types of memory.

[0106] Systems and / or devices have been described (or will be described) herein with respect to interactions between multiple components. It should be recognized that such systems and components may include those components or subcomponents designated therein, some of the designated components or subcomponents, and / or additional components. Subcomponents may also be implemented as components communicatively coupled to other components rather than being included in a parent component. Still further, one or more components and / or subcomponents may be combined into a single component that provides aggregate functionality. Components may also interact with one or more other components not specifically described herein for brevity but known to those skilled in the art.

[0107] 13 illustrates a flow diagram of one example of a non-limiting method 1300 that may control coupling between a first quantum component and a second quantum component in accordance with various aspects and embodiments of the disclosed subject matter. Method 1300 may be performed, for example, by a coupler device or system (e.g., a computer system) that includes or is operably coupled to device-forming components, a processor component, and a memory. Repeated descriptions of similar elements utilized in other embodiments described herein are or may be omitted for the sake of brevity.

[0108] At 1302, excitation of a first vibrational mode of the coupler device may be controlled based on whether a pulse is applied to the coupler device, where the coupler device may include a first vibrational mode and a second vibrational mode that may be opposite to the first vibrational mode, and the coupler device may be electrically connected between the first quantum component and the second quantum component. A device-forming component may connect the coupler device (e.g., the coupler component) to the first quantum component at one end of the coupler device and to the second quantum component at the other end of the coupler device. In some embodiments, the coupler device may be a ZZAP coupler device, such as a facemon coupler device as described herein. In other embodiments, the coupler device may be an L4ZZAP coupler device as described herein. There may be a ZZ gate that can be controlled (e.g., created or suppressed) between the first quantum component and the second quantum component via the coupler device. According to various embodiments, the first quantum component and the second quantum component may be qubits or other types of electronic elements in an electronic circuit (e.g., a quantum circuit) in which control of the coupling between the first quantum component and the second quantum component is desired (e.g., wanted).

[0109] At 1304, creation of a ZZ gate between the first quantum component and the second quantum component can be controlled based on controlling the excitation of the first vibrational mode. For example, based on controlling the excitation of the first vibrational mode and the relationship between the first vibrational mode and the second vibrational mode (e.g., the second vibrational mode is opposite to the first vibrational mode), activation status of the ZZ gate of the first quantum component and the second quantum component, and therefore creation of the ZZ gate, can be controlled. Regarding the relationship between the two modes, in some embodiments, the first vibrational mode and the second vibrational mode can have opposite signs of coupling with respect to the first quantum component and the second quantum component. When no pulse is supplied to the coupler device, the coupler device can be in a ground state (e.g., the first vibrational mode and the second vibrational mode can be in a ground state), and as a result, the second vibrational mode can interfere with the first vibrational mode and the ZZ gate can be inactive, which can cancel, inhibit, suppress, or interrupt coupling between the first qubit and the second qubit. When a pulse (e.g., an RF or π pulse) is supplied to the coupler device (e.g., via a charge line), a first vibrational mode may be excited and an imbalance may be created between the first vibrational mode and the second vibrational mode. As a result, a ZZ gate may be activated (e.g., opened or created) and coupling may exist between the first quantum component (e.g., a first qubit or other type of quantum component) and the second quantum component (e.g., a second qubit or other type of quantum component).

[0110] 14 illustrates a flow diagram of one example of a non-limiting method 1400 that may utilize a multi-JJ coupler component (e.g., a facemon coupler component) that may control coupling between a first qubit and a second qubit in accordance with various aspects and embodiments of the disclosed subject matter. Method 1400 may be performed, for example, by a coupler device or system (e.g., a computer system) that includes or is operably coupled to a device-forming component, a processor component, and / or a memory, and / or by the coupler component. Repeated descriptions of similar elements utilized in other embodiments described herein are or may be omitted for brevity.

[0111] In 1402, the first JJ, the second JJ, and the third JJ may be arranged with respect to one another in a quantum circuit to form a coupler component such that the first JJ and the second JJ may be symmetric with respect to one another, such symmetry between the first JJ and the second JJ may facilitate creation of a first mode of oscillation and a second mode of oscillation, and the third JJ may facilitate splitting between the first mode and the second mode. As described herein and illustrated in the figures, a device forming component may form (e.g., fabricate) a coupler component (e.g., a facemon coupler component utilizing a ZZ gate) to comprise three JJs, and may structure, design, and / or arrange the first JJ and the second JJ to be symmetric or at least substantially symmetric with respect to one another in the quantum circuit, and arrange the third JJ with respect to the first and second JJs in the quantum circuit such that the third JJ may facilitate splitting between the first mode and the second mode during operation of the coupler component.

[0112] At 1404, a first qubit and a second qubit may be formed in a quantum circuit. Device forming components may form the first qubit and the second qubit in the quantum circuit. In some embodiments, the first and second qubits may be transmon qubits.

[0113] At 1406, a first qubit may be connected to a first end of a coupler component, and a second qubit may be connected to a second end of the coupler component. The device forming components may connect the first qubit to a first end (e.g., a first port or lead) of the coupler component and the second qubit to a second end (e.g., a second port or lead) of the coupler component in a quantum circuit. A ZZ gate may be present between the first qubit and the second qubit through the coupler component. In some embodiments, the first mode of oscillation may be an even mode and the second mode of oscillation may be an odd mode (or vice versa), which may provide opposite signs of coupling between the first qubit and the second qubit.

[0114] In 1408, in response to no pulse being applied to the coupler component, the first mode of oscillation and the second mode of oscillation may be transitioned to or maintained at a ground state, such that the second mode of oscillation may interfere with the first mode of oscillation, the ZZ gate may be inactive, and there may be no coupling between the first qubit and the second qubit. For example, when no pulse is applied to the coupler component, the second mode of oscillation may interfere with the first mode of oscillation, such that the coupling between the first qubit and the second qubit may be canceled, or the coupling may at least substantially be canceled.

[0115] At 1410, in response to a pulse (e.g., an RF or π pulse) being applied to the coupler component, a first mode of oscillation may be transitioned from a ground state to an excited state, and as a result, the ZZ gate may be active, and coupling may exist between the first qubit and the second qubit. For example, if a charge line in the quantum circuit applies a pulse to the coupler component, a first mode of oscillation may be transitioned from a ground state to an excited state, and an imbalance may be created between the first mode of oscillation and the second mode of oscillation. As a result, the ZZ gate may be transitioned from an inactive state (e.g., a closed state) to an active state (e.g., an open state), and coupling may exist between the first qubit and the second qubit.

[0116] For simplicity of explanation, methods and / or computer-implemented methods are depicted and described as a series of actions. It is understood and appreciated that the disclosed subject matter is not limited by the depicted actions and / or the order of actions; for example, actions may occur in various orders and / or simultaneously, along with other actions not shown and described herein. Moreover, not all depicted actions may be required to implement a computer-implemented method in accordance with the disclosed subject matter. In addition, those skilled in the art will understand and appreciate that a computer-implemented method could alternatively be represented as a series of interrelated states via a state diagram or events. Additionally, it should be further appreciated that the computer-implemented methods disclosed below and throughout this specification can be stored on an article of manufacture to facilitate transferring and migrating such computer-implemented methods to a computer. The term article of manufacture, as used herein, is intended to encompass a computer program accessible from any computer-readable device or storage medium.

[0117] To provide context for various aspects of the disclosed subject matter, FIG. 15 and the following discussion are intended to provide a general description of a suitable environment in which various aspects of the disclosed subject matter may be implemented. FIG. 15 illustrates a block diagram of an example non-limiting operating environment capable of facilitating one or more embodiments described herein. Repeated descriptions of similar elements utilized in other embodiments described herein may be omitted or omitted for the sake of brevity. Referring to FIG. 15, a suitable operating environment 1500 for implementing various aspects of the present disclosure may also include a computer 1512. The computer 1512 may also include a processing unit 1514, a system memory 1516, and a system bus 1518. The system bus 1518 couples system components, including, but not limited to, the system memory 1516, to the processing unit 1514. The processing unit 1514 may be any of a variety of available processors. Dual microprocessors and other multiprocessor architectures may also be utilized as the processing unit 1514. The system bus 1518 may be any of several types of bus structures, including a memory bus or memory controller, a peripheral or external bus, and / or a local bus using any of a variety of available bus architectures, including, but not limited to, Industry Standard Architecture (ISA), MicroChannel Architecture (MSA), Enhanced ISA (EISA), Intelligent Drive Electronics (IDE), VESA Local Bus (VLB), Peripheral Component Interconnect (PCI), Card Bus, Universal Serial Bus (USB), Advanced Graphics Port (AGP), Firewire (IEEE 1394), and Small Computer System Interface (SCSI). The system memory 1516 may also include volatile memory 1520 and nonvolatile memory 1522. The basic input / output system (BIOS), containing the basic routines for transferring information between elements within the computer 1512, such as during start-up, is stored in the nonvolatile memory 1522.By way of example, and not limitation, non-volatile memory 1522 may include read-only memory (ROM), programmable ROM (PROM), electrically programmable ROM (EPROM), electrically erasable programmable ROM (EEPROM), flash memory, or non-volatile random access memory (RAM) such as ferroelectric RAM (FeRAM). Volatile memory 1520 may also include random access memory (RAM) that acts as external cache memory. By way of example, and not limitation, RAM is available in many forms, including static RAM (SRAM), dynamic RAM (DRAM), synchronous DRAM (SDRAM), double data rate SDRAM (DDR SDRAM), enhanced SDRAM (ESDRAM), Synchlink DRAM (SLDRAM), direct Rambus RAM (DRRAM), direct Rambus dynamic RAM (DRDRAM), and Rambus dynamic RAM (RDRAM).

[0118] The computer 1512 may also include removable / non-removable, volatile / non-volatile computer storage media. FIG. 15 shows, for example, disk storage 1524. Disk storage 1524 may also include devices such as, but not limited to, a magnetic disk drive, a floppy disk drive, a tape drive, a Jaz drive, a Zip drive, an LS-100 drive, a flash memory card, or a memory stick. Disk storage 1524 may also include storage media separately or in combination with other storage media, including, but not limited to, an optical disk drive, such as a compact disc read-only memory (CD-ROM), a CD-recordable drive (CD-R drive), a CD-rewriteable drive (CD-RW drive), or a digital versatile disc read-only memory (DVD-ROM). A removable or non-removable interface, such as interface 1526, is typically used to facilitate connection of the disk storage 1524 to the system bus 1518. FIG. 15 also illustrates software that acts as an intermediary between users and the basic computer resources described in the preferred operating environment 1500. Such software may also include, for example, operating system 1528. Operating system 1528, which may be stored on disk storage 1524, acts to control and allocate resources of the computer 1512. System applications 1530 take advantage of the management of resources by operating system 1528 through program modules 1532 and program data 1534, which are stored, for example, either in system memory 1516 or on disk storage 1524. It should be appreciated that the present disclosure may be implemented with various operating systems or combinations of operating systems. A user enters commands or information into computer 1512 through input devices 1536.The input devices 1536 include, but are not limited to, pointing devices such as a mouse, trackball, stylus, touchpad, keyboard, microphone, joystick, gamepad, satellite dish, scanner, television tuner card, digital camera, digital video camera, webcam, etc. These and other input devices connect to the processing unit 1514 through the system bus 1518 via interface ports 1538. Interface ports 1538 include, for example, serial ports, parallel ports, game ports, and universal serial bus (USB). The output devices 1540 use several of the same types of ports as the input devices 1536. Thus, for example, a USB port may be used to provide input to the computer 1512 and to output information from the computer 1512 to the output device 1540. An output adapter 1542 is provided to illustrate that there are some output devices 1540, such as monitors, speakers, and printers, among other output devices 1540, that require special adapters. Output adapters 1542 include, by way of example and not limitation, video and sound cards that provide a method of connection between output device(s) 1540 and the system bus 1518. It should be noted that other devices and / or systems of devices provide both input and output capabilities, such as remote computer(s) 1544.

[0119] The computer 1512 may operate in a networked environment using logical connections to one or more remote computers, such as a remote computer 1544. The remote computer 1544 may be a computer, a server, a router, a network PC, a workstation, a microprocessor-based device, a peer device, or other common network node, and the like, and may typically include many or all of the elements described relative to the computer 1512. For purposes of simplicity, only a memory storage device 1546 is shown with the remote computer 1544. The remote computer 1544 is logically connected to the computer 1512 through a network interface 1548 and, in turn, physically connected via communication connection 1550. The network interface 1548 encompasses wired and / or wireless communication networks such as a local area network (LAN), a wide area network (WAN), a cellular network, and the like. LAN technologies include Fiber Distributed Data Interface (FDDI), Copper Distributed Data Interface (CDDI), Ethernet, Token Ring, and the like. WAN technologies include, but are not limited to, point-to-point links, circuit-switched networks such as Integrated Services Digital Networks (ISDN) and its variations, packet-switched networks, and Digital Subscriber Lines (DSL). Communications connection(s) 1550 refers to the hardware / software utilized to connect network interface 1548 to system bus 1518. For clarity of illustration, communications connection(s) 1550 is shown internal to computer 1512, but could also be external to computer 1512. The hardware / software for connecting to network interface 1548 could also include, by way of example only, internal and external technologies such as ordinary telephone-grade modems, cable modems, modems including DSL modems, ISDN adapters, Ethernet cards, etc.

[0120] One or more embodiments may be a system, method, apparatus, and / or computer program product at any possible level of technical detail of integration. A computer program product may include a computer-readable storage medium (or media) having computer-readable program instructions for causing a processor to execute aspects of one or more embodiments. A computer-readable storage medium may be a tangible device capable of holding and storing instructions for use by an instruction execution device. A computer-readable storage medium may be, for example, but not limited to, an electronic storage device, a magnetic storage device, an optical storage device, an electromagnetic storage device, a semiconductor storage device, or any suitable combination of the foregoing. A non-exhaustive list of more specific examples of computer-readable storage media may include portable computer diskettes, hard disks, RAM, ROM, erasable programmable read-only memory (EPROM or flash memory), SRAM, portable CD-ROMs, digital versatile disks (DVDs), memory sticks, floppy disks, machine-encoded devices such as punch cards or raised structures in grooves with instructions recorded thereon, and any suitable combination of the above. As used herein, a computer-readable storage medium should not be construed as being a transitory signal per se, such as an electric wave or other freely propagating electromagnetic wave, an electromagnetic wave propagating through a waveguide or other transmission medium (e.g., a light pulse passing through a fiber optic cable), or an electrical signal transmitted through a wire.

[0121] The computer-readable program instructions described herein may be downloaded from a computer-readable storage medium to each computing / processing device or to an external computer or external storage device via a network, such as the Internet, a local area network, a wide area network, and / or a wireless network. The network may comprise copper transmission cables, optical fiber transmissions, wireless transmissions, routers, firewalls, switches, gateway computers, and / or edge servers. A network adapter card or network interface within each computing / processing device receives the computer-readable program instructions from the network and forwards the computer-readable program instructions to a computer-readable storage medium within the respective computing / processing device for storage. The computer-readable program instructions for performing operations of the disclosed subject matter may be either assembler instructions, instruction set architecture (ISA) instructions, machine instructions, machine-dependent instructions, microcode, firmware instructions, state setting data, configuration data for integrated circuits, or source code or object code written in any combination of one or more programming languages, including object-oriented programming languages ​​such as Smalltalk, C++, or the like, and conventional procedural programming languages ​​such as the “C” programming language or similar programming languages. The computer-readable program instructions may execute entirely on the user's computer, partially on the user's computer, as a stand-alone software package, partially on the user's computer and partially on a remote computer, or entirely on a remote computer or server. In the latter scenario, the remote computer may be connected to the user's computer through any type of network, including a local area network (LAN) or a wide area network (WAN), or the connection may be to an external computer (e.g., through the Internet using an Internet Service Provider).In some embodiments, to carry out aspects of the disclosed subject matter, an electronic circuit including, for example, a programmable logic circuit, a field programmable gate array (FPGA), or a programmable logic array (PLA) may execute computer-readable program instructions by utilizing state information of the computer-readable program instructions to personalize the electronic circuit.

[0122] Aspects of the disclosed subject matter are described herein with reference to flowchart illustrations and / or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of the present disclosure. It will be understood that each block of the flowchart illustrations and / or block diagrams, and combinations of blocks in the flowchart illustrations and / or block diagrams, can be implemented by computer-readable program instructions. These computer-readable program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, or other programmable data processing apparatus to create a machine. The instructions, which execute on the processor of the computer or other programmable data processing apparatus, thereby create a method for implementing the function(s) / act(s) specified in the block(s) of the flowchart illustrations and / or block diagrams. These computer-readable program instructions can also be stored on a computer-readable storage medium that can instruct a computer, programmable data processing apparatus, and / or other device to function in a particular manner, such that the computer-readable storage medium having the instructions stored therein comprises a product containing instructions that implements aspects of the function(s) / act(s) specified in the block(s) of the flowchart illustrations and / or block diagrams. The computer-readable program instructions may also be loaded into a computer, other programmable data processing apparatus, or other device to cause the computer, other programmable apparatus, or other device to perform a series of operational acts to create a computer-implemented process, such that the instructions executing on the computer, other programmable apparatus, or other device implement the functions / acts specified in one or more blocks of the flowcharts and / or block diagrams.

[0123] The flowcharts and block diagrams in the figures illustrate the architecture, functionality, and operation of possible implementations of systems, methods, and computer program products according to various embodiments of the disclosed subject matter. In this regard, each block in a flowchart or block diagram may represent a module, segment, or portion of instructions, including one or more executable instructions for implementing the specified logical function(s). In some alternative implementations, the functions described in the blocks may occur out of the order depicted in the figures. For example, two blocks shown in succession may be executed substantially simultaneously, depending on the functionality involved, or the blocks may be executed in the reverse order in some cases. It should also be noted that each block of the block diagrams and / or flowchart diagrams, and combinations of blocks in the block diagrams and / or flowchart diagrams, may be implemented by a dedicated hardware-based system that performs the specified functions or actions or executes a combination of dedicated hardware and computer instructions.

[0124] Although the subject matter has been described above in the general context of computer-executable instructions for a computer program product executing on a computer and / or multiple computers, those skilled in the art will recognize that the present disclosure can also be implemented in combination with other program modules. Generally, program modules include routines, programs, components, data structures, etc. that perform particular tasks and / or implement particular abstract data types. Furthermore, those skilled in the art will recognize that the computer-implemented methods disclosed herein can be practiced with other computer system configurations, including single-processor or multiprocessor computer systems, minicomputing devices, mainframe computers, computers, handheld computing devices (e.g., PDAs, phones), microprocessor-based or programmable consumer or industrial electronics, etc. The illustrated aspects can also be practiced in distributed computing environments where tasks are performed by remote processing devices linked through a communications network. However, some, if not all, aspects of the present disclosure can be practiced on stand-alone computers. In a distributed computing environment, program modules can be located in local and remote memory storage devices.

[0125] As used herein, terms such as “component,” “system,” “platform,” and “interface” may refer to and / or include computer-related entities or entities associated with an operating machine having one or more specific functionalities. The entities disclosed herein may be hardware, a combination of hardware and software, software, or software in execution. For example, a component may be, but is not limited to, a process running on a processor, a processor, an object, an executable, a thread of execution, a program, and / or a computer. By way of example, both an application running on a server and the server may be a component. One or more components may reside within a process and / or thread of execution; a component may be localized on one computer and / or distributed between two or more computers. In other examples, each component may execute from various computer-readable media having various data structures stored thereon. Components may communicate via local and / or remote processing, for example, according to signals comprising one or more data packets (e.g., data from one component interacting with other components in a local system, a distributed system, and / or other systems via signals over a network such as the Internet). As another example, a component may be a device having specific functionality provided by mechanical parts operated by electrical or electronic circuitry operated by software or firmware applications executed by a processor. In such cases, the processor may be internal or external to the device and may execute at least a portion of the software or firmware application. As yet another example, a component may be a device that provides its inherent functionality without mechanical parts but through electronic components that may include a processor or other means for executing software or firmware that provides at least a portion of the functionality of the electronic component.In one aspect, the component can emulate an electronic component via a virtual machine, for example, in a cloud computing system.

[0126] Furthermore, the term "or" is intended to mean an inclusive "or" rather than an exclusive "or." That is, unless specifically stated otherwise or clear from context, "X uses A or B" is intended to mean any of the natural inclusive permutations. That is, if X uses A; X uses B; or X uses both A and B, then "X uses A or B" is satisfied under any of the foregoing plural cases. Furthermore, as used in this specification and the accompanying drawings, the articles "a" and "an" should generally be construed to mean "one or more" unless otherwise specified or clear from context that the singular is intended. As used herein, the terms "example" and / or "exemplary" are utilized to mean serving as an example, instance, or illustration. For the avoidance of doubt, the subject matter disclosed herein is not limited to such examples. Additionally, any aspect or design described herein as "example" and / or "exemplary" is not necessarily to be construed as preferred or superior over other aspects or designs, and is not intended to exclude equivalent exemplary structures and techniques known to those skilled in the art.

[0127] The term "processor," as used herein, may refer to virtually any computing processing unit or device, including, but not limited to, a single-core processor; a single processor with software multithreading execution capabilities; a multi-core processor; a multi-core processor with software multithreading execution capabilities; a multi-core processor with hardware multithreading technology; a parallel platform; and a parallel platform with distributed shared memory. Additionally, a processor may refer to an integrated circuit, an application-specific integrated circuit (ASIC), a digital signal processor (DSP), a field-programmable gate array (FPGA), a programmable logic controller (PLC), a complex programmable logic device (CPLD), discrete gate or transistor logic, discrete hardware components, or any combination thereof designed to perform the functions described herein. Furthermore, a processor may utilize nanoscale architectures, such as, but not limited to, molecular and quantum dot-based transistors, switches, and gates, to optimize space utilization or improve performance of user equipment. A processor may also be implemented as a combination of computing processing units. In this disclosure, terms such as “memory,” “storage,” “data store,” “data storage,” “database,” and substantially any other information storage component associated with the operation and functionality of a component are utilized to refer to a “memory” or “memory component” entity embodied in a component that includes memory. It should be appreciated that the memory and / or memory components described herein may be either volatile memory or nonvolatile memory, or may include both volatile and nonvolatile memory. By way of example and not limitation, nonvolatile memory may include ROM, PROM, EPROM, EEPROM, flash memory, or nonvolatile RAM (e.g., FeRAM). Volatile memory may include RAM, which may act as external cache memory, for example.By way of example, and not limitation, RAM is available in many forms, such as SRAM, DRAM, SDRAM, DDR SDRAM, ESDRAM, SLDRAM, DRRAM, DRDRAM, and RDRAM. Additionally, the disclosed memory components of systems or computer-implemented methods herein are intended to include, but are not limited to, these and any other suitable types of memory.

[0128] The foregoing includes merely exemplary systems and computer-implemented methods. Of course, it is not possible to describe every conceivable combination of components or computer-implemented methods for purposes of describing the present disclosure, but one of ordinary skill in the art will recognize that many more combinations and permutations of the present disclosure are possible. Furthermore, when terms such as "comprises," "having," and "comprises" are used in the detailed description, claims, appendices, and drawings, such terms are intended to be inclusive in the same manner as the term "comprises" is interpreted when used as a transitional phrase in a claim. The description of various embodiments has been presented for illustrative purposes and is not intended to be exhaustive or limited to the disclosed embodiments. Many modifications and variations will be apparent to those skilled in the art without departing from the scope and spirit of the described embodiments. The terminology used herein has been selected to best explain the principles of the embodiments, practical applications, or technical improvements over technologies found in the marketplace, or to enable others skilled in the art to understand the embodiments disclosed herein.

Claims

1. a first electronic element; a second electronic element; and a coupler component connected to the first electronic element and the second electronic element, wherein the coupler component has a first Josephson junction, a second Josephson junction, and a third Josephson junction associated with the first Josephson junction and the second Josephson junction in a quantum circuit, and the coupler component has a first mode of oscillation and a second mode of oscillation based on the relationship between the first Josephson junction, the second Josephson junction, and the third Josephson junction in the quantum circuit; A device comprising:

2. 2. The device of claim 1, wherein a geometry between the first Josephson junction and the second Josephson junction in the quantum circuit forces the first mode to have a first sign of coupling and the second mode to have a second sign of coupling with respect to the first electronic element and the second electronic element, the second sign being opposite to the first sign.

3. 10. The device of claim 9, wherein the first Josephson junction and the second Josephson junction are substantially similar, the first Josephson junction being located between a first capacitive pad and a third capacitive pad, the second Josephson junction being located between a second capacitive pad and the third capacitive pad, and the third Josephson junction being located between the third capacitive pad and a ground element.

4. the first electronic element is connected to a fourth capacitive pad and is capacitively coupled to the coupler component via the first capacitive pad and the fourth capacitive pad; The second electronic element is connected to a fifth capacitive pad and is capacitively coupled to the coupler component via the second capacitive pad and the fifth capacitive pad. The device of claim 3.

5. 10. The device of claim 9, wherein a first frequency associated with the first mode or a second frequency associated with the second mode is defined based on a parameter associated with the third Josephson junction and a geometry between the first Josephson junction, the second Josephson junction, and the third Josephson junction in the quantum circuit.

6. 10. A device according to any preceding claim, wherein the first electronic element and the second electronic element are associated with a range of frequencies above the frequency of the coupler component.

7. 10. A device according to any preceding claim, wherein the first electronic element and the second electronic element are associated with a range of frequencies below the frequency of the coupler component.

8. a coupler component associated with a first quantum component and a second quantum component, wherein the coupler component: Josephson junctions; and a resonator associated with the Josephson junction, wherein the Josephson junction is associated with a first mode of vibration and the resonator is associated with a second mode of vibration. device.

9. 9. The device of claim 8, wherein the resonator is a Lambda / 4 type resonator, and wherein, for the first quantum component and the second quantum component, the first mode is associated with a first sign of coupling and the second mode is associated with a second sign of coupling, the second sign being different from the first sign.

10. 10. The device of claim 8, wherein the Josephson junction is located between a first capacitance pad and a second capacitance pad, the resonator is a Lambda / 4 type resonator, an inductor of the Lambda / 4 type resonator is in parallel with the Josephson junction, the Lambda / 4 type resonator is connected to a ground element, and the Lambda / 4 type resonator is associated with a third capacitance pad and a fourth capacitance pad.

11. 11. The device of claim 10, wherein the first quantum component is connected to a fifth capacitive pad and is capacitively coupled to the coupler component via the first capacitive pad and the fifth capacitive pad, and the second quantum component is connected to a sixth capacitive pad and is capacitively coupled to the coupler component via the second capacitive pad and the sixth capacitive pad.

12. controlling excitation of a first vibrational mode of a coupler device based on whether a pulse is applied to the coupler device, the coupler device having the first vibrational mode and a second vibrational mode that is opposite to the first vibrational mode, the coupler device being electrically connected between a first quantum component and a second quantum component; and controlling creation of a ZZ gate between the first quantum component and the second quantum component based on the controlling of the excitation of the first vibrational mode. A method comprising:

13. applying the pulse to the coupler device; creating the excitation of the first vibrational mode of the coupler device in response to applying the pulse to the coupler device; and creating the ZZ gate between the first quantum component and the second quantum component in response to creating the excitation of the first vibrational mode. The method of claim 12 further comprising:

14. 14. The method of claim 12, wherein ZZ interaction or coupling between the first quantum component and the second quantum component is suppressed in response to no pulse being applied to the coupler device.

15. 15. The method of claim 12, wherein the coupler device comprises a first Josephson junction, a second Josephson junction, and a third Josephson junction in a circuit, the first Josephson junction and the second Josephson junction being substantially symmetrical, and based on the first Josephson junction and the second Josephson junction being substantially symmetrical, the first vibrational mode has a first sign of coupling and the second vibrational mode has a second sign of coupling, the second sign being opposite to the first sign, with respect to the first quantum component and the second quantum component, and the splitting between the first vibrational mode and the second vibrational mode is based on a parameter associated with the third Josephson junction.

16. the parameter is a first parameter, a fourth Josephson junction is connected in parallel with the second Josephson junction in the circuit, a coil component is proximate to the second Josephson junction and the fourth Josephson junction in the circuit, and the method further comprises: supplying a current to the coil component; generating a magnetic flux in response to the current being supplied to the coil component; applying the magnetic flux to the second Josephson junction or the fourth Josephson junction; and adjusting a second parameter associated with the second Josephson junction in response to applying the magnetic flux. The method of claim 15, comprising:

17. 17. The method of claim 12, wherein the coupler device comprises a Josephson junction and a Lambda / 4 resonator, the Josephson junction being associated with the first vibrational mode and the Lambda / 4 resonator being associated with the second vibrational mode, and the first vibrational mode being associated with a first sign of coupling and the second vibrational mode being associated with a second sign of coupling, the second sign being different from the first sign, with respect to the first quantum component and the second quantum component.

18. the Josephson junction is a first Josephson junction, a second Josephson junction is connected in parallel with the first Josephson junction, a coil component is proximate to the first Josephson junction and the second Josephson junction, and the method further comprises: supplying a current to the coil component; generating a magnetic flux in response to the current being supplied to the coil component; applying the magnetic flux to the first Josephson junction or the second Josephson junction; and adjusting a parameter associated with the first Josephson junction in response to applying the magnetic flux.

20. The method of claim 17, comprising:

19. First qubit; a second qubit; and a coupler device associated with the first qubit and the second qubit, the coupler device having a first mode of oscillation and a second mode of oscillation, an activation status of a ZZ gate between the first qubit and the second qubit being managed based on an excitation status of the first mode and a relationship between the first mode and the second mode, the excitation status being based on whether a pulse is applied to the coupler device; A system comprising:

20. the coupler device having a first Josephson junction, a second Josephson junction, and a third Josephson junction associated with the first Josephson junction and the second Josephson junction in a circuit; the first mode and the second mode are based on the substantial symmetry of the first Josephson junction and the second Josephson junction and on a parameter associated with the third Josephson junction; Based on the substantial symmetry of the first Josephson junction and the second Josephson junction, for the first qubit and the second qubit, the first mode has a first sign of coupling and the second mode has a second sign of coupling, the second sign being opposite to the first sign.

20. The system of claim 19.

21. 21. The system of claim 19, wherein the coupler device comprises a Josephson junction and a Lambda / 4 type resonator, the Josephson junction being associated with the first oscillation mode and the Lambda / 4 type resonator being associated with the second mode, and wherein, for the first qubit and the second qubit, the first mode is associated with a first sign of coupling and the second oscillation mode is associated with a second sign of coupling, the second sign being opposite to the first sign.

22. 22. The system of claim 19, wherein the pulse is a radio frequency pulse, and wherein in response to the radio frequency pulse being applied to the coupler device, the first mode is excited, and based on the first mode being excited, the ZZ gate between the first qubit and the second qubit is activated to enable ZZ interaction or coupling between the first qubit and the second qubit.

23. 23. The system of claim 19, wherein the pulse is a radio frequency pulse, and the coupler device is driven resonantly based on the radio frequency pulse applied to the coupler device.

24. 24. The system of claim 19, wherein the first mode and the second mode are in a non-excited state in response to no pulse being applied to the coupler device, and based on the first mode and the second mode being in a non-excited state, the ZZ gate is inactive and ZZ interaction or coupling between the first qubit and the second qubit is suppressed.

25. a coupler component associated with the first electronic element and the second electronic element, the coupler component comprising: a first coupler element; and Second Coupler Element wherein the coupler component has a first mode associated with a first frequency and a second mode associated with a second frequency, and based on a relationship between the first coupler element and the second coupler element, the second mode can be an inverse of the first mode.

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