Quantum computer phase tracking and correction

Abstract

The invention relates to a controller for a quantum system that identifies a phase update trigger and an interaction time for a quantum object of the quantum system. In response to identifying the phase update trigger, the controller determines, between a first time and the interaction time, (a) a position / transmission effect on a phase of the quantum object based on a position of the quantum object and a transmission operation performed thereon, and (b) a quantum operation effect on the phase of the quantum object based on any quantum operations applied to the quantum object. An immediately preceding phase update of the quantum object occurs at the first time. An interaction time phase of the quantum object is determined by the controller based on the position / transmission effect, the quantum operation effect, and the interaction time. The controller adjusts an operation of a steering source such that a phase of a signal generated by the steering source corresponds to the interaction time phase at the interaction time.

Description

TECHNICAL FIELD

[0001] Various embodiments relate to tracking phases of quantum objects (e.g., qubits) within a quantum system and performing phase corrections on quantum system manipulation sources. For example, various embodiments relate to qubit phase tracking in a quantum computer. BACKGROUND

[0002] Quantum systems require the use of quantum mechanics to accurately describe the temporal evolution of quantum objects, and a phase can be used to at least partially describe a quantum state of a quantum object. In various quantum systems, quantum objects of the quantum system can experience various environmental effects, which can cause the phase of the quantum object to differ from a passive phase evolution (e.g., in the absence of electromagnetic fields and / or other environmental effects) over time. For example, if ions of a quantum system are qubits of a trapped-ion quantum computer, the qubits can experience various environmental effects related to electric and / or magnetic fields and temperature, depending on the location or region / segment of the ion trap in which the qubit is located. These environmental effects can affect the phase of the qubit. Moreover, when quantum operations (e.g., gates) are performed on a qubit, energy can be added to the qubit, which also affects the phase of the qubit. SUMMARY

[0003] According to a first aspect, a method is provided. In an example embodiment, the method includes identifying, by a controller corresponding to a quantum system, a phase update trigger for a particular quantum object of the quantum system. The quantum object is an atom or an ion. The phase update trigger corresponds to an interaction time. The method further includes, in response to identifying the phase update trigger, determining, by the controller, a location and transport effect on a phase of the particular quantum object based on one or more locations of the particular quantum object and one or more transport operations performed on the particular quantum object between a first time and the interaction time; and determining, by the controller, a quantum operation effect on the phase of the particular quantum object based on any quantum operations applied to the particular quantum object between the first time and the interaction time. The immediate previous phase update of the particular quantum object occurred at the first time. The method further includes determining, by the controller and based on the location and transport effect, the quantum operation effect, and the interaction time, an interaction time phase of the particular quantum object. The method further includes causing, by the controller, a phase of one or more signals (a) to be generated by one or more manipulation sources and (b) to correspond to the phase update trigger to be adjusted, such that the phase of the one or more signals corresponds to the interaction time phase of the particular quantum object at the interaction time.

[0004] In example embodiments, one or more signals are incident on a particular quantum object at an interaction time. In example embodiments, the one or more manipulation sources include at least one of: (a) one or more lasers or (b) one or more voltage sources. In example embodiments, the quantum operation effect corresponds to a Stark shift. In example embodiments, the quantum system is part of a trapped-ion quantum computer and the particular quantum object is a qubit of the trapped-ion quantum computer. In example embodiments, a phase of a signal of the one or more signals corresponds to an interaction-time phase of the particular quantum object when an absolute value of a difference between the phase of the signal and the interaction-time phase of the particular quantum object satisfies a phase-difference-value threshold requirement. In example embodiments, the absolute value of the difference between the phase of the signal and the interaction-time phase satisfies the phase-difference-value threshold requirement when the absolute value of the difference between the phase of the signal and the interaction-time phase is less than a set phase-difference-value threshold. In example embodiments, a phase update trigger is identified by determining that application of the one or more signals to the particular quantum object or qubit is scheduled to occur at the interaction time. In example embodiments, identifying a phase update trigger corresponding to the particular quantum object, determining a position and transport effect of a phase of the particular quantum object, determining a quantum operation effect on the phase of the particular quantum object, and causing an adjustment of a phase of the one or more signals are performed in real-time or near real-time with respect to one another. In example embodiments, the position and transport effect corresponds to a phase change due to a change in an effective frequency of the particular quantum object based on one or more positions of the particular quantum object and a transport of the particular quantum object through the one or more positions between a first time and the interaction time.

[0005] According to another aspect, a controller associated with a quantum system is provided. In one example embodiment, the controller includes at least one processing element and at least one memory including / storing computer program code. The at least one memory and the computer program code are configured to, with the processing element, cause the controller to at least identify a particular quantum object for the quantum system and a phase update trigger corresponding to an interaction time. The at least one memory and the computer program code are further configured to, with the processing element, cause the controller to at least in response to identifying the phase update trigger, determine a position and transport effect on a phase of the particular quantum object based on one or more positions of the particular quantum object and one or more transport operations performed on the particular quantum object between a first time and the interaction time; determine a quantum operation effect on the phase of the particular quantum object based on any quantum operations applied to the particular quantum object between the first time and the interaction time; determine an interaction time phase of the particular quantum object based on the position and transport effect, the quantum operation effect, and the interaction time; cause a phase of one or more signals (a) to be generated by one or more steering sources and (b) to correspond to the phase update trigger to be adjusted, such that the phase of the one or more signals corresponds to the interaction time phase of the particular quantum object at the interaction time. An immediately preceding phase update of the particular quantum object occurs at the first time.

[0006] In example embodiments, the one or more signals are incident on the particular quantum object at an interaction time. In example embodiments, the one or more manipulation sources include at least one of: (a) one or more lasers or (b) one or more voltage sources. In example embodiments, the quantum operation effect corresponds to a Stark shift. In example embodiments, the quantum system is part of a trapped-ion quantum computer and the particular quantum object is a qubit of the trapped-ion quantum computer. In example embodiments, a phase of a signal of the one or more signals corresponds to an interaction-time phase of the particular quantum object when an absolute value of a difference between the phase of the signal and the interaction-time phase of the particular quantum object satisfies a phase-difference-value threshold requirement. In example embodiments, the absolute value of the difference between the phase of the signal and the interaction-time phase satisfies the phase-difference-value threshold requirement when the absolute value of the difference between the phase of the signal and the interaction-time phase is less than a set phase-difference-value threshold. In example embodiments, a phase update trigger is identified by determining that application of the one or more signals to the particular quantum object or qubit is scheduled to occur at the interaction time. In example embodiments, identifying a phase update trigger corresponding to the particular quantum object, determining a position and transport effect of a phase of the particular quantum object, determining a quantum operation effect on the phase of the particular quantum object, and causing an adjustment of a phase of the one or more signals are performed in real-time or near real-time with respect to one another. In example embodiments, the position and transport effect corresponds to a phase change due to a change in an effective frequency of the particular quantum object based on one or more positions of the particular quantum object and a transport of the particular quantum object through the one or more positions between a first time and the interaction time. BRIEF DESCRIPTION OF DRAWINGS

[0007] Accordingly, having generally described the application, reference will now be made to the drawings, which are not necessarily drawn to scale, and wherein:

[0008] Figure 1 A schematic diagram of an example quantum computer system in accordance with example embodiments is provided.

[0009] Figure 2A A schematic diagram of an example of tracking a phase change of a qubit based on a position and / or transport of the qubit in accordance with example embodiments is provided; and

[0010] Figure 2B A flowchart in accordance with one example embodiment is provided, showing an example process, procedure, and / or operation of tracking a phase change of a qubit due to Figure 2A An example of an example process, procedure, and / or operation of tracking a phase change of a qubit due to a position and / or transport of the qubit in accordance with the examples provided in the

[0011] Figure 3A diagram showing an example of tracking a quantum bit phase change due to applying a signal generated by a manipulation source to a quantum bit is provided in accordance with an example embodiment.

[0012] Figure 4 is a flowchart showing an example process, procedure, and / or operation for tracking a phase of a quantum bit and correcting a phase of a signal to be applied to the quantum bit, performed by a controller such as Figure 8

[0013] Figure 4A is a diagram showing how environmental effects experienced by a quantum object can differ based on a location of the quantum object within a quantum system.

[0014] Figure 5 An example scenario of performing a single quantum bit gate and a two quantum bit gate on four quantum bits is shown in accordance with an example embodiment.

[0015] Figure 6 A diagram of an example user computing entity that can be used in accordance with an example embodiment is provided.

[0016] Figure 7 A diagram of an example system computing entity that can be used in accordance with an example embodiment is provided.

[0017] Figure 8 A diagram of an example controller that can be used in accordance with an example embodiment is provided. DETAILED DESCRIPTION

[0018] The present application now will be described more fully hereinafter with reference to the accompanying drawings, in which some, but not all embodiments of the applications are shown. Indeed, the applications can be embodied in many different forms and should not be construed as limited to the embodiments set forth herein; rather, these embodiments are provided so that this disclosure will satisfy applicable legal requirements. The term "or" (also "and / or") is used herein in the alternative (either / or) and conjunctive (both) senses, unless otherwise indicated. The terms "exemplary" and "example" are used herein to mean an example or illustration, not an ideal. The terms "generally" and "approximately" are used herein to refer to within appropriate engineering and / or manufacturing tolerances and / or within user measurement capabilities, unless otherwise indicated. Like numbers refer to like elements throughout.

[0019] ​As described above, quantum objects of a quantum system can experience various environmental effects that can affect the phase of the quantum objects. In various embodiments, the quantum system is part of a quantum computer, and the quantum objects are qubits of the quantum computer. For example, the quantum system can be used to perform quantum computations and / or quantum operations. For example, the quantum system can be part of a superconducting quantum computer, and the quantum objects are states of small superconducting circuits. In another example, the quantum system can be part of a trapped ion quantum computer and / or an optical lattice quantum computer, and the quantum objects are atomic objects (e.g., atoms or ions). In another example, the quantum system is part of a photonic-based quantum computer, and the quantum objects are photons. In the example of qubits of a trapped ion quantum computer, the qubits can experience various environmental effects related to electric and / or magnetic fields and temperature depending on the location or region of the ion trap in which the qubit is located, which affect the phase of the qubit. Moreover, when performing quantum operations (e.g., gates) on the qubits within the quantum computer, energy can be added to the qubits, which can also affect the phase of the qubits. However, if a manipulation source (e.g., a voltage source, a laser, a direct digital synthesis (DDS), etc.) applies a signal (e.g., a voltage, a laser beam, etc.) to the qubit where the phase of the signal does not correspond to the phase of the qubit, the qubit can jitter. Such jitter of the qubit can directly affect qubit coherence, qubit gate fidelity, and overall quantum computer error rates.

[0020] Exemplary embodiments provide methods, apparatuses, and systems for tracking the phase of quantum objects of a quantum system and correcting the phase of a signal of a manipulation source to be applied to the quantum objects. As used herein, a quantum object can be an atom, ion, or other object or particle that is trapped within and / or manipulated within a quantum system. For example, various embodiments provide methods, apparatuses, and systems for tracking the phase of qubits of a trapped ion quantum computer and correcting the phase of a signal of a manipulation source (e.g., a voltage source, a laser beam, a DDS, etc.) applied to the qubits. In various embodiments, the phase tracking is performed in real-time or near real-time. For example, in response to identifying a phase update trigger during operation of the quantum computer, the phase of a particular qubit can be determined. In various embodiments, because the phase tracking is performed in real-time or near real-time (e.g., during operation of the quantum computer), branches of a quantum algorithm / program being executed are enabled. For example, the real-time or near real-time phase tracking of various embodiments enables quantum algorithms / programs to be changed, branched, etc., during execution of the quantum algorithms / programs.

[0021] In various embodiments, a quantum computer (or other quantum system) includes a transport-enabled ion trap. For example, the quantum system can be within the transport-enabled ion trap. For example, the quantum computer (or other quantum system) includes an ion trap having a plurality of regions, and a qubit (or other quantum object) can be transported between one or more of the plurality of regions defined within the ion trap. In various embodiments, an effect on a phase of the qubit due to a location of the qubit within the ion trap and / or a transport of the qubit can be tracked. In various embodiments, an application of a quantum operation (e.g., a quantum gate applied via one or more laser beams incident on and / or interacting with the qubit) can cause the qubit to experience a phase shift (e.g., corresponding to a Stark shift). Various embodiments determine a phase of the qubit and / or a change in the phase of the qubit based on the location of the qubit and / or the transport of the qubit and the application of the quantum operation (and / or other signals generated by a manipulation source) to the qubit.

[0022] In various embodiments, a phase of a qubit is determined in response to a phase update trigger being identified. For example, in response to identifying a phase update trigger, a change in the phase of a particular qubit since a last phase determination of the particular qubit and / or a phase update can be determined. In an example embodiment, a phase update trigger can be identified by determining that a command corresponding to an application of a signal to be generated by a manipulation source to a particular qubit has been scheduled, is scheduled to be executed within a particular time window, is scheduled to occur for the particular qubit as a next event (a next event to be executed by a controller), and / or the like. In various embodiments, a phase update trigger is identified in response to determining that a signal is scheduled to be provided to a particular qubit by a manipulation source. A phase of the qubit at an interaction time (e.g., at the interaction time) can be determined, and a phase of the signal provided by the manipulation source can be modified and / or adjusted such that the phase of the signal will correspond to the phase of the qubit when the signal is incident on and / or interacts with the qubit (e.g., at the interaction time). In one example embodiment, the phase of the signal corresponds to the phase of the qubit when the phase of the signal and the phase of the qubit match each other and / or are approximately equal. For example, the phase of the signal corresponds to the phase of the qubit when an absolute value of a difference between the phase of the signal and the phase of the corresponding qubit is less than or equal to a threshold phase difference value s ( e.g., | φ q - φ T | ≤ Δ φ s ). In various embodiments, when the threshold phase difference value Δ φ q is made smaller (e.g., set closer to zero), performance of the quantum system (e.g., robustness and / or repeatability of results) is improved. T s q T is made smaller (e.g., set closer to zero), performance of the quantum system (e.g., robustness and / or repeatability of results) is improved.​​​

[0023] As described above, in various quantum systems, it is important to apply a signal generated by a manipulation source to a quantum object of the quantum system such that a phase of the signal corresponds to, matches, and / or approximately equals a phase of the quantum object at the time the signal interacts with the quantum object. Various embodiments provide for tracking of a phase of a quantum object of a quantum system and phase correction of a signal generated by a manipulation source to be applied to the quantum object. In various embodiments, the tracking of the phase of the quantum object and the phase correction of the signal are performed in real-time and / or near real-time with respect to manipulation of the quantum object of the quantum system (e.g., via application of the signal to the quantum object). Various exemplary embodiments correspond to a trapped ion quantum computer system, tracking of a phase of a qubit of the trapped ion quantum computer, and phase correction of a signal applied to the qubit. In various embodiments, the tracking of the phase of the qubit and the phase correction of the signal are performed in real-time and / or near real-time with respect to interaction of the signal with the qubit of the trapped ion quantum computer.

[0024] Example quantum computer system

[0025] Figure 1 A schematic diagram of an exemplary quantum system according to exemplary embodiments is provided, wherein the quantum system is part of a trapped ion quantum computer system 100. In various embodiments, the trapped ion quantum computer system 100 includes a user computing entity 10, a system computing entity 20, and a quantum computer 110. In various embodiments, the quantum computer 110 includes a controller 30, a cryogenic and / or vacuum chamber 40 enclosing an ion trap 50, and a manipulation system 60 including one or more manipulation sources (e.g., lasers, voltage sources, DDS, etc.). In various embodiments, the manipulation system 60 is configured to provide one or more signals (e.g., signals generated by manipulation sources 64 (e.g., 64A, 64B, 64C)) to one or more qubits within the ion trap 50 via signal paths 66 (e.g., 66A, 66B, 66C). In various embodiments, the signals 66 include one or more of optical paths, optical fibers, electrical cables, etc. In various embodiments, one or more calibration sensors 62 can be coupled to one or more manipulation sources 64 and / or signal paths 66 configured to monitor one or more operational characteristics of the corresponding manipulation source 64 and / or signal and provide an indication of the results of monitoring the one or more operational characteristics to the controller 30.

[0026] In various embodiments, user computing entities 10 are configured to allow users to provide input to quantum computer system 100 (e.g., via a user interface of user computing entity 10) and are configured to receive, visualize, etc. output from quantum computer system 100. User computing entities 10 can communicate with system computing entity 20 via one or more wired or wireless networks 120. System computing entity 20 is configured to act as an intermediary between one or more user computing entities 10 and controller 30. For example, system computing entity 20 can translate, configure, format (and / or otherwise process) information / data, quantum computing algorithms, etc. provided by user computing entities 10 into a computational language, executable instructions, command sets, etc. that controller 30 can understand and / or implement.

[0027] In various embodiments, controller 30 is configured to control ion trap 50, a cooling and / or vacuum system (not shown) that controls temperature and pressure within cryogenic and / or vacuum chamber 40, manipulation source 64, and / or other components of quantum computer 110 (e.g., an optical collection system configured for “reading” output of the quantum computer). In various embodiments, controller 30 is configured to control various components of quantum computer 110 in accordance with executable instructions, command sets, etc. provided by system computing entity 20. In various embodiments, controller 30 is configured to receive output from quantum computer 110 (e.g., from the optical collection system) and provide the output and / or results of processing the output to system computing entity 20.

[0028] In various embodiments, controller 30 includes a clock. Controller 30 can receive one or more executable instructions, commands, etc., and each executable instruction, command, etc. is scheduled to be executed at a particular time determined by the clock. One or more of the executable instructions, commands, etc. can correspond to a manipulation event. A manipulation event includes causing a signal (e.g., generated by a manipulation source 64) to interact with one or more qubits. The interaction can be scheduled by the controller to occur at an interaction time. In various embodiments, a schedule of computer executable instructions, commands, etc. corresponding to and / or resulting in a manipulation event (e.g., application of one or more signals (e.g., generated by one or more manipulation sources 64) to a particular qubit and / or pair / group of qubits) at an interaction time can be identified as a phase update trigger corresponding to the particular qubit and / or pair / group of qubits. In example embodiments, a determination that a computer executable instruction, command, etc. corresponding to and / or resulting in a manipulation event (e.g., application of one or more signals (e.g., generated by one or more manipulation sources 64) to a particular qubit and / or pair / group of qubits) is scheduled to be executed at an interaction time (within a time threshold of a current time (e.g., as determined by the clock)) can result in identification of a phase update trigger. In example embodiments, a determination that a next set / group of computer executable instructions, commands, etc. corresponding to and / or resulting in a manipulation event (e.g., application of one or more signals (e.g., generated by one or more manipulation sources 64) to a particular qubit and / or pair / group of qubits) is scheduled to be executed by the controller can result in identification of a phase update trigger corresponding to the particular qubit and / or pair / group of qubits.

[0029] In response to the identification of the phase update trigger corresponding to the interaction time and the particular qubit and / or pair / group of qubits, the controller 30 can determine a position and / or transport effect and / or phase change for the particular qubit and / or each qubit of the pair / group of qubits. In various embodiments, the phase of the particular qubit and / or pair / group of qubits can be tracked as a phase accumulation for each qubit. The position and / or transport effect and / or phase change corresponds to a position of the qubit and / or a transport between positions of the qubit occurring between a first time and the interaction time. The first time is a time at which an immediately preceding interaction time of the qubit occurred. Additionally, the controller 30 can determine a quantum operation effect and / or phase change for the particular qubit and / or each qubit of the pair / group of qubits. The quantum operation effect and / or phase change of the qubit is due to any quantum operation (e.g., quantum gate, laser beam, etc.) applied to the qubit between the first time and the interaction time. For example, the quantum operation effect and / or phase change can be a Stark shift of the qubit due to a laser beam impinging on the qubit. The interaction time phase (e.g., the phase expected / determined at the interaction time) for the particular qubit and / or each qubit of the pair / group of qubits can then be determined based on the corresponding immediately preceding determined phase of the qubit (e.g., determined in response to an immediately preceding identified phase update trigger corresponding to the particular qubit and / or an initialization step corresponding to the particular qubit), the position and / or transport effect, and the quantum operation effect.

[0030] The controller 30 can then cause the phase of the signal to be applied to the particular qubit and / or pair / group of qubits during the scheduled maneuver event to be adjusted to correspond to the interaction time phase of the particular qubit and / or pair / group of qubits. For example, the controller 30 can reset the maneuver source 64, cause the operation of the maneuver source 64 to be modified and / or adjusted, etc., such that the phase of the signal generated by the maneuver source 64 corresponds to the interaction time phase of the particular qubit at the interaction time (e.g., when the signal interacts with and / or impinges on the particular qubit).

[0031] Examples of location and / or transport effect determinations

[0032] Examples of determining a position and / or transport effect of a phase of one or more quantum objects will now be described with respect to an example trapped ion quantum computer 110. Figure 2A A schematic diagram of a qubit 200 in a two-region ion trap is provided. Figure 2B A flowchart showing an example scenario in which a qubit 200 is located in an ion trap and transported between regions of the ion trap and corresponding phases of the qubit 200 is provided. In Figure 2B In the example scenario provided, a gate applied to the qubit 200 does not affect the phase of the qubit. For example, with respect toFigure 2B The gate can be a microwave gate. However, due to magnetic field gradients across the ion trap and / or other environmental effects, the phase of the qubit can evolve differently in different regions or in regions of the ion trap. It will be appreciated that the ion trap can have multiple qubits therein, and the phase of each qubit can be tracked.

[0033] In an example scenario, at step / operation 221, the qubit 200 is initialized in the first region 201 of the ion trap at time tl according to the clock of the controller 30. The qubit 200 is initialized to have a phase φ1=0. The qubit record (e.g., stored in a memory of the controller 30) can be updated to indicate that at time tl, the qubit 200 has a phase φ1=0.

[0034] The qubit 200 remains in the first region 201, and at time t2, a gate (e.g., a quantum operation) is applied to the qubit 200 via the first DDS 211 at step operation 222. While in the first region 201, the effective frequency of the qubit 200 is a first frequency f1. The first frequency f1 can be influenced by environmental factors (e.g., applied voltages, experienced magnetic fields, temperature, frequency of the first DDS 211, etc.) corresponding to the first region 201. Thus, the phase of the qubit 200 at time t2 is given by φ2=[φ1+2πf1(t2-t1)] mod 2π. In various embodiments, the phase is defined modulo 2π. For example, the phase of the qubit 200 at time t2 is φ2=[φ1+2πf1(t2-t1)] mod 2π, where φ1=0. i+1 i+1 = [φ i + Δφ] mod 2π, where φ i is the phase of the qubit 200 at an immediately preceding time t i prior to updating the qubit record corresponding to the qubit 200, and Δφ is a change in phase between time t i and time t i+1 . When φ1=0, due to the initial step performed at time tl, the phase of the qubit 200 at time t2 is φ2=2πf1(t2-t1) mod 2π.

[0035] Between time t2 and time t3, the qubit 200 is transported from the first region 201 to the second region 202 at step / operation 223. During the transport of the qubit 200 from the first region 201 to the second region 202, the frequency of the qubit is given by a transport frequency function F T , which is a function of the position of the qubit 200 between the first region 201 and the second region 200. In an example embodiment, the transport frequency function F T is assumed to be a constant effective transport frequency f T ​For example, in various embodiments, the transmission frequency function F T is assumed and / or approximated as a constant effective transmission frequency f T along the path from the first region 201 to the second region 202. T In example embodiments, the transmission frequency function F T (x), where x is a position between the first region 201 and the second region 202. Generally, φ2= F gives the accumulated phase of the qubit during the transmission operation that transmits the qubit 200 from the first region 201 to the second region 202. Thus, in example embodiments, at time t3, where F T may be approximated as a constant effective transmission frequency f T , the phase of the qubit 200 is given by φ3= [φ2+ 2πf T (t3-t2)] mod 2π upon completion of the transmission operation that transmits the qubit from the first region 201 to the second region 202.

[0036] At time t4, a gate is performed on the qubit 200 in the second region 202 by the second DDS 212 at step / operation 224. While in the second region 202, the effective frequency of the qubit 200 is a second frequency f2. In various embodiments, the second frequency f2 is influenced by environmental factors (e.g., applied voltage, experienced magnetic field, temperature, frequency of the second DDS 212, etc.) corresponding to the second region 202. In various embodiments, the second frequency f2 can be different from the first frequency f1 and / or the transmission frequency f T . Thus, at time t4, the phase of the qubit 200 is φ4= [φ3+ 2πf2(t4-t3)] mod 2π. Although not described in detail herein, a phase correction (e.g., for a signal generated by the second DDS 212) corresponding to the application of the gate to the qubit 200 at time t4 can be performed based on the phase of the qubit at time t4.

[0037] In example scenarios, at step / operation 225, the qubit 200 is transmitted from the second region 202 to the first region 201 from time t4 to time t5. Thus, at time t5, upon completion of the transmission operation that transmits the qubit from the second region 202 to the first region 201, the phase of the qubit 200 is given by φ5= [φ4+ 2πf T (t5-t4)] mod 2π.

[0038] At step / operation 226, at time t6, a gate is applied to qubit 200 in the first region 201. In an exemplary scenario, between time t5 and time t6, qubit 200 remains in the first region 201, where the effective frequency of qubit 200 is f1. Therefore, the phase of qubit 200 at time t6 is φ6 = [φ5 + 2πf1(t6 - t5)] mod 2π. In various embodiments, phase correction may be performed corresponding to applying a gate to qubit 200 at time t6. For example, the first DDS 211 may operate at a first frequency f1. Thus, as time has progressed from time t1 to time t6, when the phase of the first DDS 211 is finally adjusted to correspond to the phase of qubit 200 at that time, where the first DDS 211 applies another gate to qubit 200, the phase φ of the first DDS 211... source It has evolved into φ source = 2πf1(t6-t1)mod 2π. In the same time interval, the phase φ of qubit 200... qubit It has evolved into φ qubit =2π[f1(t2-t1)+f T (t3-t2)+f2(t4-t3)+f T [(t5-t4)+f1(t6-t5)]mod 2π. Therefore, if f2≠f1 mod 2π or f T If f1 mod 2π, then the phase φ of the first DDS 211 is ≠ f1 mod 2π. source Phase φ with qubit 200 qubit The phases will be unequal, matched, and / or similar. For example, the phase φ of the first DDS 211. source The phase φ with qubit 200 qubit Asynchronous. If the phase φ of the first DDS 211 is determined... source Phase φ with qubit 200 qubit The absolute value of the difference between them does not meet the phase change threshold (e.g., If the phase of the first DDS 211 is adjusted to correspond to, match, and / or approximately equal to the phase of the qubit 200, then the phase of the first DDS 211 can be shifted such that the phase of the first DDS 211 is approximately equal to the phase of the qubit 200. In an exemplary embodiment, the phase of the first DDS 211 is set to be approximately equal to the phase of the qubit 200.

[0039] As mentioned above, in scenarios where there are no quantum manipulation effects on the phase of a qubit, qubit 200 at time t i+1 The phase at φ i+1 =[φ i +Δφ]mod 2π, where φi is the phase of qubit 200 at a time t i immediately prior to the time t i at which qubit 200 is updated to record the phase of qubit 200 at a time t i+1 and / or a change in phase accumulation due to the position of qubit 200 and / or transport of qubit 200 between regions between times t

[0040] Examples of quantum operation effect determinations

[0041] Examples of determining quantum operation effects on one or more quantum objects will now be described with respect to an example trapped-ion quantum computer 110. Figure 3 A schematic diagram showing examples of determining quantum operation effects on the phase of a qubit and correcting the phase of a signal generated by a manipulation source (e.g., applying a gate to a qubit) is provided. In the illustrated scenario, a qubit is initialized at a time t0. Between times tl and t2, a microwave gate is applied to the qubit, as shown by line 304. For example, a microwave pulse can interact with the qubit between times tl and t2. The microwave signal generator frequency is constant at all times, as shown by line 306. As shown by lines 310 and 312, applying the microwave gate to the qubit does not affect the qubit phase or the qubit frequency.

[0042] From time t3 to t4, a laser beam and / or pulse generated by a frequency- shifting laser can be incident on and / or interact with the qubit, as shown by line 302. For example, between times t3 and t4, the frequency-shifting laser can emit a signal that interacts with the qubit. In example embodiments, the frequency-shifting laser is a laser whose frequency shifts the frequency of the qubit when the laser beam, pulse, and / or signal generated by the laser interacts with the qubit. For example, when the laser beam, pulse, and / or signal generated by the frequency-shifting laser interacts with the qubit, the qubit experiences a Stark shift. For example, as shown by line 310, from time t3 to t4, the frequency of the qubit shifts from its unshifted frequency f0 to an operation-induced frequency that is different from and / or not equal to the unshifted frequency f0. For example, the interaction of the laser beam, laser pulse, and / or signal generated by the frequency-shifting laser can shift the frequency of the qubit by a shift value f g such that the shifted frequency of the qubit is f0+ f gFor example, as shown by line 312, during the time that the laser beam, laser pulse, and / or signal generated by the frequency-shifted laser interacts with the qubit (e.g., between times t3 and t4), the phase of the qubit evolves to a different phase than it would have if the qubit had not interacted with the laser beam, laser pulse, and / or signal generated by the frequency-shifted laser. For example, when the qubit interacts with the laser beam, laser pulse, and / or signal generated by the frequency-shifted laser, the phase of the qubit evolves between times t3 and t4 according to (f0 + f g ) At = f0 At + f g At = f0 At + p, where At = t4 - t3. In contrast, if the qubit had not interacted with the laser beam, laser pulse, and / or signal generated by the frequency-shifted laser (e.g., if the frequency of the qubit had remained at the unshifted frequency), the phase of the qubit would have evolved between times t3 and t4 according to f 0Δt .

[0043] For example, as shown by the comparison of lines 306 and 310, for all times that the qubit does not interact with the laser beam, laser pulse, and / or signal generated by the frequency-shifted laser (e.g., times other than between t3 and t4), the microwave signal generator frequency and the qubit frequency coincide with each other. For example, as shown by lines 308 and 312, the microwave signal generator phase and the qubit phase coincide with each other from time t0 to time t3. Then, between times t3 and t4, when the qubit interacts with the laser beam, laser pulse, and / or signal generated by the frequency-shifted laser, the phase of the qubit is shifted relative to the microwave signal generator phase such that there is a difference p between the qubit phase and the microwave signal generator phase at time t4.

[0044] At time t5, a second microwave gate is applied to the qubit, as shown by line 304. The microwave signal source phase is adjusted so that the second microwave gate is applied to the qubit so that the phase of the microwave signal source at time t5 corresponds to the phase of the qubit. For example, at some point between times t4 and t5, the controller 30 can identify a phase update trigger that corresponds to the qubit and to the interaction time of time t5. In response to identifying the phase update trigger that corresponds to the qubit and to the interaction time of time t5, the controller can determine the quantum operation effect on the phase of the qubit of applying the laser beam, laser pulse, and / or signal generated by the frequency-shifted laser to the qubit. For example, the controller 30 can determine that applying the laser beam, laser pulse, and / or signal generated by the frequency-shifted laser to the qubit results in p = (f0 + f g ) At - f0 At = f ga phase shift of At. Thus, when a microwave gate is applied to the qubit at time ts, the microwave signal generator phase can be shifted by the phase shift p. For example, as shown by line 308, the microwave signal generator phase is shifted by p, such that the signal provided by the microwave signal generator (e.g., acting as a second microwave gate) has a phase corresponding to the phase of the qubit at the time of interaction (e.g., time ts).

[0045] Thus, Figure 3 Examples are provided of determining a phase shift of a quantum operation effect on a phase of a qubit and resetting a phase of a manipulation source (e.g., the microwave signal generator in the illustrated example) such that, at a time of interaction, a signal generated by the manipulation source and a qubit that interacts with the signal have corresponding phases.

[0046] Example real-time or near real-time phase tracking and correction

[0047] In various embodiments, performing real-time and / or near real-time phase tracking and correction includes tracking position and / or transport effects on one or more quantum objects and quantum operation effects. Figure 4 Flowcharts are provided showing various processes, procedures, operations, etc. for performing real-time or near real-time phase tracking and correction in accordance with various embodiments, with an example quantum system being a part of trapped ion quantum computer 110. In various embodiments, a controller 30 corresponding to the quantum system can perform phase tracking and correction with respect to quantum objects of the quantum system and manipulation sources of the quantum system. For example, in various embodiments, real-time or near real-time phase tracking and correction is performed by controller 30 of trapped ion quantum computer 110 to track phases of qubits of trapped ion quantum computer 110 and adjust phases of signals generated by manipulation sources 64 (e.g., lasers, voltage sources, DDS, etc.) and / or phases of manipulation sources 64 such that, when a signal generated by a manipulation source interacts with a qubit, the phase of the signal corresponds to the phase of the qubit.

[0048] Figure 4A An example quantum system 450 is shown in which environmental effects (e.g., magnetic fields and / or other environmental effects) vary across quantum system 450. A first quantum object 452A in region A of quantum system 450 experiences a first magnetic field 454A. A second quantum object 452B in region B of quantum system 450 experiences a second magnetic field 454B, and a third quantum object 452C in region C of quantum system 450 experiences a third magnetic field 454C. As shown, first magnetic field 454A, second magnetic field 454B, and third magnetic field 454C are different. For example, first magnetic field 454A, second magnetic field 454B, and third magnetic field 454C can differ in direction and / or amplitude. Thus, as shown, first quantum object 452A, second quantum object 452B, and third quantum object 452C experience different magnetic fields. Figure 4A Figure 4A ​As shown, the environmental effects can vary on the quantum system 450. Additionally, as noted above, quantum operations (e.g., gates) performed and / or conducted on one or more quantum objects can also affect the phase of the one or more quantum objects. Thus, in various embodiments, both the position and / or transport phase effects as well as the quantum operation phase effects are tracked and / or corrected.

[0049] From Figure 4 Initially, at step / operation 402, after initialization of the one or more qubits within the ion trap 50, the position of each qubit within the ion trap 50 of the trapped-ion quantum computer is tracked. For example, the controller 30 can track the region of the ion trap 50 in which each of the one or more qubits is located, the amount of time the qubit is located within the region (e.g., based on a clock of the controller 30), the amount of time the qubit is transported between regions (e.g., based on a clock of the controller 30), quantum operations applied to the qubit, etc. For example, the controller 30 can receive computer-executable instructions, commands, etc. from the system computing entity 20. The controller 30 can then schedule the executable instructions, commands, etc. to be executed at a particular time (e.g., based on a clock of the controller 30) (e.g., in an executable queue of the controller 30). The controller 30 can then execute the executable instructions, commands, etc. in the controller’s executable queue at the scheduled particular time.

[0050] In various embodiments, the controller 30 stores a qubit record for each of the one or more qubits in the ion trap 50 (e.g., in the memory 810 of the controller 30). For example, each qubit within the ion trap 50 can be associated with a qubit identifier. A qubit record can be stored for each of the one or more qubits within the ion trap 50 storing position and / or transport information / data, phase accumulation information / data, quantum operation information / data, etc. and indexed by the qubit identifier. The controller 30 can update the qubit record corresponding to a particular qubit (e.g., indexed by the qubit identifier corresponding to the particular qubit) (e.g., stored in the memory 810 of the controller 30) as each time the particular qubit is operated (e.g., transported from one region to another, has a quantum operation applied to it, etc.) to accumulate the phase of the particular qubit, updating the position and / or transport information / data of the particular qubit (e.g., the amount of time the qubit is located within a region, the region in which the qubit is located, the amount of time the qubit is transported between regions, etc.), the quantum operation information / data of the particular qubit (e.g., the quantum operations applied to the qubit, how the quantum operations are applied to the qubit, etc.). In various embodiments, the phase information / data of the qubit record can be updated in response to identification of a phase update trigger corresponding to the qubit.

[0051] In example embodiments, the qubit record can be a log corresponding to all activity of a particular qubit performed during a session of operating the quantum computer 110. In example embodiments, the qubit record can indicate when the phase of the qubit has been updated so that the next time the phase of the qubit is updated, the update can be performed forward from the immediately previous update (e.g., without having to update the phase of the qubit from when the qubit was launched). In one example embodiment, the qubit record is overwritten when a phase update is performed. For example, each time a phase update is performed for a particular qubit, the corresponding qubit record is erased clean and starts over.

[0052] At step / operation 404, a phase update trigger is identified by the controller 30. In various embodiments, the phase update trigger corresponds to one or more qubits (e.g., which can include a particular qubit that is to be operated in a particular manner) and can also correspond to an interaction time. In various embodiments, the phase update trigger corresponding to a particular qubit is identified in response to a computer executable instruction, command, etc. (e.g., by the controller 30) corresponding to and / or causing the occurrence of a manipulation event (e.g., the application of one or more signals (e.g., generated by one or more manipulation sources 64) to a particular qubit) being scheduled for execution at an interaction time. In example embodiments, the phase update trigger corresponding to a particular qubit is identified in response to a determination (e.g., by the controller 30) that a computer executable instruction, command, etc. corresponding to and / or causing the occurrence of a manipulation event (e.g., the application of one or more signals (e.g., generated by one or more manipulation sources 64) to a particular qubit) is scheduled for execution at a time threshold from a current time (e.g., determined by a clock). In example embodiments, the phase update trigger corresponding to a particular qubit can be identified in response to a determination (e.g., by the controller 30) that a next set / group of computer executable instructions, commands, etc. scheduled for execution by the controller 30 corresponding to and / or causing the occurrence of a manipulation event will result in the application of a signal and / or quantum operation to a particular qubit. In example embodiments, a phase update trigger can be identified corresponding to a particular qubit or a particular region of the ion trap 50. For example, a phase update trigger can indicate that a phase accumulation / update should be performed on all qubits located within a particular region of the ion trap 50 (e.g., based on corresponding qubit records). In example embodiments, such a phase update trigger (e.g., corresponding to a particular region of the ion trap 50) can be identified in response to the application of a gate to one or more qubits within the particular region of the ion trap 50.

[0053] Accordingly, in various embodiments, the controller 30 can identify a phase update trigger that corresponds to one or more qubits (e.g., including a particular qubit) and possibly to an interaction time based on computer executable instructions, commands, etc. scheduled to be executed by the controller 30. Each set / group of computer executable instructions, commands, etc. is scheduled to be executed at an interaction time corresponding to a manipulation event. The scheduled interaction time for executing computer executable instructions, commands, etc. corresponding to and / or resulting in a manipulation event is extracted from the execution queue of the controller 30 and associated with the identified phase update trigger as an interaction time associated with and / or corresponding to the identified phase update trigger. A qubit identifier identifying the particular qubit as a subject of the manipulation event is extracted from the computer executable instructions, commands, etc. and associated with the identified phase update trigger to identify the particular qubit associated with and / or corresponding to the identified phase update trigger. When the phase update trigger corresponds to a particular region of an ion trap, the controller can query the qubit record to determine which qubits are located within the particular region and identify those qubits corresponding to the qubit record indicating that the qubit is located within the particular region as being associated with and / or corresponding to the identified phase update trigger.

[0054] At step / operation 406, a position and / or transport effect on the phase of each of the one or more qubits (e.g., including a particular qubit) can be determined by the controller 30. For example, the controller 30 can use the position and / or transport information / data stored in the qubit record corresponding to the particular qubit to determine a position and / or transport effect on the phase of the particular qubit over a time period between the time at which the phase information and / or data stored in the qubit record corresponding to the particular qubit was last updated and the interaction time. For example, as described above, the position and / or transport effect on the phase of the particular qubit can be determined by multiplying the amount of time the particular qubit spends in a particular region or transporting between regions by the frequency at which the particular qubit is in the particular region or transported between regions and summing each region and / or transport between regions that occurs over the time period between the time at which the phase information and / or data stored in the qubit record corresponding to the particular qubit was last updated and the interaction time. The position and / or transport information / data of the qubit record provides the amount of time the particular qubit spends in a particular region and an indicator of the particular region and the amount of time the particular qubit spends transporting between regions. The frequency at which the particular qubit is in a particular region or transporting between regions can be determined based on a calibration table.

[0055] In various embodiments, controller 30 can store (e.g., in memory 810) a calibration table that indicates a region frequency for each region of ion trap 50. In one example embodiment, the region frequency for a region is the frequency of a qubit when the qubit is located within the region. In various embodiments, magnetic field gradients and / or other environmental effects can cause the region frequency of a first region to be different than the region frequency of a second region that is adjacent to and / or contiguous with the first region. In various embodiments, the calibration table indicates a transport frequency for each pair of adjacent regions. In one example embodiment, the transport frequency corresponding to a first region and an adjacent and / or contiguous second region is the frequency of a qubit when the qubit is transported from the first region to the second region. In one example embodiment, the transport frequency is given as a function of time and / or distance along a transport path from the first region to the adjacent and / or contiguous second region. In such embodiments, the transport frequency can be integrated over the transport path to determine the effect on the phase of a qubit of transporting the qubit from the first region to the second region.

[0056] In various embodiments, the calibration table is periodically and / or regularly calibrated. For example, the calibration table can be generated, updated, populated (and / or otherwise processed) based on sensor measurements captured by a calibration sensor 62 (e.g., 62A, 62C) coupled to quantum computer 110. For example, calibration sensor 62 can be coupled to quantum computer 110 such that calibration sensor 62 monitors one or more operating characteristics of a manipulation source and / or a signal generated by the manipulation source, and provides a signal to controller 30 indicative of the monitored operating characteristics. In various embodiments, calibration sensor 62 can be a frequency sensor, a voltage sensor, a power sensor, etc. For example, the frequency of a voltage source can be determined by calibration sensor 62 coupled to the voltage source. Similarly, the power of a signal (e.g., generated by a manipulation source 64) can be determined by calibration sensor 62 coupled to manipulation source 64, signal path 66, etc. corresponding to the signal. In various embodiments, the calibration table can be generated, updated, populated (and / or otherwise processed) at the beginning of each operating session of quantum computer 110 (e.g., each time a quantum object is added to ion trap 50, at the beginning of an execution of a quantum algorithm, etc.). In example embodiments, the calibration table is periodically updated, repopulated (and / or otherwise processed) during operation of quantum computer 110 (e.g., every thirty seconds, every minute, every two minutes, every five minutes, every ten minutes, every fifteen minutes, etc.). Thus, any drift in the power, voltage, frequency, etc. of the manipulation source and / or signals generated thereby can be monitored and accounted for within the information / data stored in the calibration table.

[0057] At step / operation 408, the controller 30 determines a quantum operation effect on the phase of the particular qubit due to any quantum operations applied to the particular qubit since the phase information / data in the qubit record corresponding to the particular qubit was last updated. For example, the controller 30 can identify any quantum operations applied to the particular qubit since the phase information / data in the qubit record corresponding to the particular qubit was last updated based on the quantum operation information / data of the qubit record. The effect of any identified quantum operations on the phase of the particular qubit can then be determined. For example, the Stark shift resulting from any identified quantum operations can be determined. In an example embodiment, the determination of the quantum operation effect includes accessing information / data from a calibration table. For example, the Stark shift experienced by a qubit due to a laser beam incident on the qubit depends on the power delivered to the qubit by the laser beam. Thus, in one example, the power of the signal applied to the particular qubit to apply the quantum operation can be accessed from the calibration table.

[0058] At step / operation 410, the controller 30 determines the phase of the particular qubit at the interaction time. For example, the controller 30 can use the determined position and / or the transmission effect Δφ LT , the determined quantum operation effect Δφ QO , and the previous phase of the particular qubit φ i from the phase information / data of the qubit record corresponding to the particular qubit to determine the interaction time phase φ i+1 of the particular qubit (e.g., the phase of the particular qubit at the interaction time) φ i+1 = [φ i + Δφ LT + Δφ QO ] mod 2π. In an example embodiment, the phase of the manipulation source and / or the signal generated by the manipulation source at the interaction time can also be determined. For example, in an example embodiment in which the phase of the manipulation source and / or the signal generated thereby is shifted (e.g., rather than set), the phase of the manipulation source and / or the signal generated thereby at the interaction time is determined so that the phase shift can be determined. For example, the phase shift is the change in phase of the manipulation source and / or the signal generated thereby that is needed to correspond to, match, and / or approximate equal to the phase of the particular qubit at the interaction time (e.g., when the signal interacts with the particular qubit).

[0059] At step / operation 412, the controller 30 causes the phase of the manipulation source 64 and / or the signal generated by the manipulation source 64 to be adjusted so that the phase of the signal generated by the manipulation source 64 corresponds to the interaction time phase when the signal interacts with the particular qubit at the interaction time. For example, the controller 30 can set the phase of the manipulation source 64 and / or the signal generated thereby (e.g., via the driver controller element 815) so that the phase of the manipulation source 64 and / or the signal generated thereby will correspond to, match, and / or approximately equal the interaction time phase of the particular qubit when the signal interacts with the particular qubit at the interaction time. For example, the controller 30 can cause the phase of the manipulation source 64 and / or the signal generated thereby to be shifted (e.g., based on the phase shift confirmed in step / operation 410 and / or via the driver controller element 815) so that the phase of the manipulation source 64 and / or the signal generated thereby will correspond to, match, and / or approximately equal the interaction time phase of the particular qubit when the signal interacts with the particular qubit at the interaction time. For example, the controller 30 can cause a voltage to be applied to the manipulation source 64 and / or a driver corresponding to the manipulation source 64 (e.g., via the driver controller element 815) that causes the phase of the manipulation source 64 and / or the signal generated by the manipulation source 64 to be adjusted so that the phase of the signal generated by the manipulation source 64 corresponds to the interaction time phase when the signal interacts with the particular qubit at the interaction time. The controller 30 can then execute computer-executable instructions, commands, etc. at the interaction time so that the manipulation event occurs (e.g., the signal is generated by the manipulation source and the signal interacts with the particular qubit) so that the phase of the signal and the phase of the particular qubit correspond to, match, and / or approximately equal each other.

[0060] In various embodiments, the phase of the steering source 64 and / or the signal generated by the steering source 64 is adjusted so that when the signal is executing a single qubit gate on a qubit, the phase of the signal generated by the steering source 64 corresponds to the interaction time phase of the qubit with which the signal is interacting. In various embodiments in which the controller 30 is configured to execute a phase-insensitive two-qubit gate, the phase of the steering source 64 and / or the signal generated by the steering source 64 is not adjusted when the signal is executing two or more qubit gates on two or more qubits. However, the Stark shift (or other phase shift) provided to the two or more qubits by the action of the two-qubit gate is tracked for future reference. In various embodiments in which the controller 30 is configured to execute a phase-sensitive two-qubit gate, two or more steering sources 64 can be used to each provide a signal that addresses a single qubit acted on by the two or more qubit gate. The phase of the steering source 64 and / or the signal generated by the steering source 64 can be adjusted so that the phase of the signal generated by the steering source 64 corresponds to the interaction time phase of the qubit addressed by that steering source 64 when the signal is interacting with that qubit. In various embodiments in which the controller 30 is configured to execute a phase-sensitive two-qubit gate, one or more correction pulses can be used to address and / or correct for phase differences between the two or more qubits acted on by the two-qubit gate.

[0061] In various embodiments, the identification of the phase update trigger, the determination of the position and / or transport effects, the determination of the quantum operation effects, the determination of the interaction time phase, and the real-time and / or near real-time adjustment of the phase of the manipulation source 64 and / or the signal generated thereby to be adjusted relative to one another are performed. In particular, the interaction time phase of a particular qubit is determined during operation of the quantum computer 110 (e.g., during execution of a quantum algorithm). For example, the interaction time phase of a particular qubit can be determined in real-time or near real-time relative to the occurrence of a manipulation event that is one-sided with respect to the particular qubit. In various embodiments, the real-time or near real-time determination of the interaction time phase of a particular qubit (relative to a manipulation event involving the particular qubit) enables the quantum algorithm being executed to be branched and / or modified during execution of the quantum algorithm. For example, the quantum algorithm can be modified on-the-fly. Additionally, in various embodiments, the determination of the interaction time phase of a particular qubit (relative to a manipulation event involving the particular qubit) based on periodically updated calibration tables enables the interaction time phase to be determined more accurately because any drift in the manipulation sources is accounted for by the information / data stored in the calibration tables. Moreover, in various embodiments, the determination of the interaction time phase based on the position and / or transport effects and the quantum operation effects allows the interaction time phase to be determined more accurately. By determining the interaction time phase more accurately, the manipulation sources 64 can be operated to provide signals having a phase that more accurately corresponds to, matches, and / or approximately equals the actual phase of a particular qubit (e.g., a threshold phase difference Δφ T may be small) thereby resulting in improved qubit coherence, qubit gate fidelity, and lower overall quantum computer error rates.

[0062] Example scenario

[0063] Figure 5 An exemplary scenario of a single qubit gate and a two-qubit gate being performed on four qubits is shown in accordance with one exemplary embodiment. In the illustrated exemplary scenario, the quantum system is part of a trapped ion quantum computer 110 and the quantum objects are ions within ion traps 50. The exemplary scenario is performed in an ion trap 50 having segments A, B, C, D, E, F, and G. In the exemplary scenario, time is only advanced during the application of quantum operations (e.g., transport operations, single qubit gate operations, two-qubit gate operations, state preparation operations, measurement operations, etc.). The processing device 805 can execute various commands to update the qubit records stored in the memory 810, each qubit record corresponding to a qubit in the quantum computer 110.

[0064] In Figure 5In the exemplary scenario shown, controller 30 is configured to use various operations and / or commands, including Configure, Transport, StatePrep, SQGate, and TQGate. In various implementations, the Measure command may also be used. The Configure command takes the position of each qubit and the frequency of each segment of trap 50 as parameters and, upon execution (e.g., by processing device 805), sets the initial qubit segments (e.g., the segments of ion trap 50 where each qubit is located), initializing the qubit phase aggregator. (For example, where the subscript q indicates a specific qubit (e.g., 0, 1, 2, or 3 in this example)), and the frequency f in each segment of the ion trap 50. S (For example, where the subscript S indicates a specific segment of the ion trap 50 (e.g., A, B, C, D, E, F, or G in this example)). For example, the current position of the qubit, the immediately preceding position of the qubit, and the qubit phase accumulator can be updated / initialized in the corresponding qubit record. The Transport command takes the segment where each qubit is located after the transport operation is complete as a parameter, and upon execution (e.g., by processing device 805), causes each qubit record to be updated such that the current position of the qubit indicates the segment indicated by the Transport command parameter, and if the qubit has moved an area, the immediately preceding position of the qubit is updated accordingly. In various embodiments, the execution of the Transport command (e.g., by processing device 805) can cause the qubit phase accumulator of one or more qubit records to be updated. Updated based on the performed transfer operation. The StatePrep command takes the segment of the ion trap 50 to be executed by the state preparation operation as a parameter, and during execution (e.g., by the processing device 805), causes the qubit record of the qubits located in the indicated segment to be updated to update the qubit phase accumulator of the qubit record. Set to 0 (e.g., to initialize the qubit phase accumulator). The SQGate command takes a section as parameters, which includes the single qubit gate to be executed, the Θ value corresponding to one or more parameters of that gate, and the phase optimization value. This Θ value can be set and / or configured by the designer and / or programmer of the quantum circuit and / or algorithm; this phase optimization value is a parameter of the single-qubit gate. In various implementations, the phase optimization value... Quantum phase accumulator that can be added to a qubit record This qubit record corresponds to the qubit acted upon by a single qubit gate when determining the interaction time phase of the qubits and the phase correction of the gate. In various implementations, the phase optimization value can be achieved through... to adjust the qubit phase accumulator of the qubit record corresponding to the qubit to be acted on by the single-qubit gate to prevent additional operations from needing to be performed on the qubits (e.g., phase correction operations, rotation of the qubit vectors on the Bloch sphere to adjust for various phase effects of the gate, etc.). Execution of the SQGate command (e.g., by the processing device 805) causes the qubit phase accumulator of the qubit record corresponding to the qubit acted on by the single-qubit gate to be updated based on the Stark shift or other quantum operation effects that affect the phase of the qubit acted on by the single-qubit gate to prevent additional operations from needing to be performed on the qubits (e.g., phase correction operations, rotation of the qubit vectors on the Bloch sphere to adjust for various phase effects of the gate, etc.). Execution of the SQGate command (e.g., by the processing device 805) causes the qubit phase accumulator of the qubit record corresponding to the qubit acted on by the single-qubit gate to be updated based on the Stark shift or other quantum operation effects that affect the phase of the qubit acted on by the single-qubit gate to prevent additional operations from needing to be performed on the qubits (e.g., phase correction operations, rotation of the qubit vectors on the Bloch sphere to adjust for various phase effects of the gate, etc.). Execution of the SQGate command (e.g., by the processing device 805) causes the qubit phase accumulator of the qubit record corresponding to the qubit acted on by the single-qubit gate to be updated based on the Stark shift or other quantum operation effects that affect the phase of the qubit acted on by the single-qubit gate based on the time since a previous command was executed.

[0065] For example, at time tl, a Configure command can be executed (e.g., by the processing device 805) to initialize the positions of the qubits and reset the qubit phase accumulators of the qubit records corresponding to the qubits The Configure command can also set the frequency of each segment (e.g., determined based on the calibration performed).

[0066] At time t2, a Transportation command can be executed (e.g., by the processing device 805). For example, the Transportation command can cause the qubit records corresponding to qubit 0 and qubit 2 to be updated based on the segments in which qubit 0 and qubit 2 change within the ion trap 50.

[0067] At time t3, a StatePrep command can be executed (e.g., by the processing device 805). The StatePrep command can act on the qubits located in particular segments of the ion trap 50 (e.g., segments B and F) to set the qubit phase accumulators of the qubit records corresponding to the qubits located in segments B and F to zero and / or to indicate that the qubit phase accumulators of the qubit records corresponding to the qubits located in segments B and F are ready and / or able to be updated / accumulated. to zero and / or to indicate that the qubit phase accumulators of the qubit records corresponding to the qubits located in segments B and F are ready and / or able to be updated / accumulated. to zero and / or to indicate that the qubit phase accumulators of the qubit records corresponding to the qubits located in segments B and F are ready and / or able to be updated / accumulated. For example, the qubit phase accumulators of the qubit records corresponding to qubit 0 and 2 located in segments B and F, respectively, are ready and / or able to be updated / accumulated. may be set to zero, and / or the qubit records corresponding to qubits 0 and 2 can be updated to indicate the qubit phase accumulator of the qubit record are ready and / or can be updated / accumulated.

[0068] At time t4, an SQGate command can be executed (e.g., by processing device 805). For example, the SQGate command can cause the interaction time phase (phase q ) of each qubit to be determined to be acted upon by one or more single qubit gates (e.g., qubits 0 and 2 located in segments B and F). This is the phase corresponding to segment B in which qubit 0 is located. For example, In an example embodiment, where f B is the trap frequency in segment B. Similarly, the interaction time phase of qubit 2 can be determined to be which is In an example embodiment, where f F is the trap frequency in segment F. After the single qubit gates are completed and / or as a result of the execution of the SQGate command, the qubit phase accumulator of the qubit records corresponding to the qubits located within the segments acted upon by the single qubit gates are updated to include the Stark shift or other quantum operation effects accumulated by the qubits as a result of being acted upon by the single qubit gates.

[0069] At time t5, a Transport command can be executed (e.g., by processing device 805). For example, the Transport command can cause the qubit records corresponding to qubits 0, 1, 2, and 3 to be updated based on the qubits changing segments and / or being transported within ion trap 50. In one example embodiment, prior to updating the location of each qubit based on the execution of the Transport command, the qubit phase accumulator of each qubit record is updated to account for the effects of the qubits being located in particular segments during the time the single qubit gates were executed. For example, the qubit phase accumulators of qubit 0 and qubit 2 may be increased by (t4-t3)*f B and (t4-t3)*f F , respectively. The execution of the Transport command can also cause the qubit phase accumulator of each qubit record to be updated based on the transport of the qubits across one or more segments of the ion trap. For example, the qubit phase accumulators of qubit 0 and qubit 2 may be increased by 2pif T(t5-t4). In an example embodiment, f T corresponding to a particular segment of ion trap 50.

[0070] At time t6, a StatePrep command can be executed (e.g., by processing device 805). The StatePrep command can act on qubits located in particular segments of ion trap 50 (e.g., segments B and F) to accumulate qubit-recorded qubit phase accumulators corresponding to qubits located in segments B and F are set to zero and / or indicate that the qubit-recorded qubit phase accumulators are ready and / or able to be updated / accumulated. For example, the qubit-recorded qubit phase accumulators corresponding to qubits 1 and 3 located in segments B and F, respectively, may be set to zero, and / or the qubit records corresponding to qubits 1 and 3 can be updated to indicate that the qubit-recorded qubit phase accumulators are ready and / or able to be updated / accumulated. In addition, execution of the StatePrep command can cause the qubit phase accumulators for qubits 0 and 2 to be updated based on a location effect. For example, the qubit phase accumulators for qubits 0 and 2 are updated based on a location effect. For example, the qubit phase accumulators for qubits 0 and 2 may be incremented by the value (t6-t5)*f A (t6-t5)*f E .

[0071] At time t7, an SQGate command can be executed (e.g., by processing device 805). For example, the SQGate command can cause the interaction time phase (phase q ) for each qubit to be determined to be acted on by one or more single-qubit gates (e.g., qubits 1 and 3 located in segments B and F). For example, the interaction time phase for qubit 1 can be determined to be which is the phase corresponding to segment B in which qubit 1 is located. For example, In an example embodiment, where f B is the trap frequency in segment B. Similarly, the interaction time phase for qubit 3 can be determined to be which is In an example embodiment, where f F is the trap frequency in segment F. After the single-qubit gates are completed and / or as a result of executing the SQGate command, the qubit-recorded qubit phase accumulators corresponding to qubits located within the segments acted on by the single-qubit gates updated to include the Stark shift or other quantum operation effects accumulated by the qubits due to the action of the single-qubit gates.

[0072] At time t8, a Transport command can be executed (e.g., by processing device 805). For example, the Transport command can cause the qubit records corresponding to qubits 0, 1, 2, and 3 to be updated based on the change in the segment within ion trap 50 in which the qubits are located. In one example embodiment, the qubit phase accumulator of each qubit record is updated prior to updating the location of each qubit based on the execution of the Transport command to account for the effect of the location of the qubits in a particular segment during the time in which the single-qubit gate is executed. For example, the qubit phase accumulator of qubit 0 can be incremented by a value of 2πf A *(t7 - t6). The execution of the Transport command can also cause the qubit phase accumulator of each qubit record to be updated based on the transport of the qubits across one or more segments of the ion trap. For example, the qubit phase accumulator of qubit 0 can be incremented by a value of 2πf T *(t8 - t7).

[0073] At time t9, a TQGate command can be executed (e.g., by processing device 805). The TQGate command corresponds to two qubit gates being executed in segment B and segment F. In the illustrated scenario, two-qubit gates that are phase insensitive are used, so there is no need to determine an interaction time phase. However, the execution of the TQGate command causes the qubit phase accumulator of each qubit record corresponding to the qubits located in segments B and F to be updated based on the Stark shift or other quantum operation effects that affect the phase of the qubits due to the execution of the two-qubit gates on the qubits. The qubit phase accumulator of each qubit record can also be updated to account for the effect of the location of the qubits in a particular segment during the time in which the two-qubit gates are executed. For example, the qubit phase accumulator of qubit 0 can be incremented by a value of f B *(t9 - t8).

[0074] It should be appreciated that Figure 5 One example of real-time or near real-time phase tracking of qubits of quantum computer 110 according to an example embodiment is illustrated, and is provided as an illustration. Based on the disclosure provided herein, a variety of other scenarios can be implemented according to various other embodiments, which will be apparent to those of ordinary skill in the art.

[0075] Technical advantages

[0076] Various embodiments provide technical solutions to the technical problem of accurately and precisely matching the phase of a signal applied to a quantum object (e.g., an atom, ion, etc.) of a quantum system to the phase of the quantum object. For example, various embodiments provide for determining the phase of a quantum object in real-time or near real-time as a signal is to interact with the quantum object, such that the operation of a manipulation source generating the signal can be modified so that the phase of the signal corresponds to, matches, and / or approximately equals the phase of the quantum object at the time of the interaction. Thus, the impact on the quantum object due to the interaction with the signal (e.g., due to the phase of the signal not matching the phase of the quantum object) can be reduced, such that the results of manipulating the quantum object (e.g., by applying the signal) provide more robust and repeatable results. Additionally, in various embodiments, determining the phase of the quantum object at the time of the interaction (relative to a manipulation event involving the quantum object) based on a periodically updated calibration table enables more accurate determination of the phase at the time of the interaction, as any drift in the manipulation source is accounted for by the information / data stored in the calibration table. Moreover, in various embodiments, the phase at the time of the interaction is determined based on position and / or transport effects as well as quantum operation effects, allowing for more accurate determination of the phase of the quantum object at the time of the interaction. By more accurately determining the phase of the quantum object at the time of the interaction, the manipulation source can be operated to provide a signal having a phase that more accurately corresponds to, matches, and / or approximately equals the actual phase of a particular qubit (e.g., a threshold phase difference Δφ T may be smaller), resulting in more robust and repeatable manipulation event results. For example, where the quantum system is part of a trapped ion quantum computer, these improvements in phase tracking and correction result in improved qubit coherence, qubit gate fidelity, and lower overall quantum computer error rates.

[0077] Moreover, real-time or near real-time determination of the phase of the quantum object at the time of the interaction allows for updating of an algorithm (a quantum algorithm executed by a quantum computer) during execution of the algorithm. Thus, various embodiments provide additional flexibility in the execution of a quantum algorithm executed by a quantum computer by enabling the quantum algorithm to be modified in real-time or near real-time relative to execution of the quantum algorithm (e.g., during execution of the quantum algorithm).

[0078] Example user computing entity

[0079] Figure 6 An example schematic of an example user computing entity 10 that can be used in connection with embodiments of the present invention is provided. In various embodiments, the user computing entity 10 is configured to allow a user to provide input to a quantum computer system 100 (e.g., via a user interface of the user computing entity 10) and is configured to receive, visualize, etc. output from the quantum computer system 100.

[0080] As shown, user computing entity 10 can include an antenna 612, a transmitter 604 (e.g., radio), a receiver 606 (e.g., radio), and a processing element 608 that provides signals to and receives signals from the transmitter 604 and receiver 606, respectively. The signals provided to and received from the transmitter 604 and receiver 606, respectively, can include signaling information / data in accordance with the air interface standards of the applicable wireless systems. In this regard, the user computing entity 10 can be capable of operating with one or more air interface standards, communication Figure 6 protocols, modulation types, and access types. More particularly, the user computing entity 10 can operate in accordance with any of a number of wireless communication standards and protocols. In particular embodiments, the user computing computer device 10 can operate in accordance with a number of wireless communication standards and protocols, such as General Packet Radio Service (GPRS), Universal Mobile Telecommunications System (UMTS), Code Division Multiple Access 2000 (CDMA2000), CDMA2000 IX (lxRTT), Wideband Code Division Multiple Access (WCDMA), Global System for Mobile Communications (GSM), Enhanced Data Rates for GSM Evolution (EDGE), Time Division-Synchronous Code Division Multiple Access (TD-SCDMA), Long Term Evolution (LTE), Evolved Universal Terrestrial Radio Access Network (E-UTRAN), Evolution-Data Optimized (EVDO), High Speed Packet Access (HSPA), High-Speed Downlink Packet Access (HSDPA), IEEE 802.11 (Wi-Fi), Wi-Fi Direct, 802.16 (WiMAX), Ultra-Wide Band (UWB), Infrared (IR) protocol, Near-Field Communication (NFC) protocol, Wibree, Bluetooth protocol, Wireless Universal Serial Bus (USB) protocol, and / or any other wireless protocol.

[0081] Via these communication standards and protocols, the user computing entity 10 can communicate with various other entities using concepts such as Unstructured Supplementary Service Data (USSD), Short Message Service (SMS), Multimedia Message Service (MMS), Dual-Tone Multi-Frequency Signaling (DTMF), and / or Subscriber Identity Module Dialer (SIM dialer). The user computing entity 10 can also download changes, plug-ins, and updates to, for example, its firmware, software (e.g., including executable instructions, applications, program modules), and operating system.

[0082] According to one embodiment, the user computing entity 10 can include location determining aspects, devices, modules, functionalities, and / or similar words used herein interchangeably. For example, the user computing entity 10 can include outdoor positioning aspects, such as a positioning module adapted to obtain, for example, latitude, longitude, altitude, geocode, heading, orientation, direction, speed, UTC, date, and / or various other information / data. In one embodiment, the positioning module can obtain data, sometimes referred to as ephemeris data, by identifying the number of satellites in view and the relative positions of those satellites. These satellites can be a variety of different satellites, including LEO satellite systems, DOD satellite systems, the European Galileo positioning system, the Chinese Beidou satellite navigation system, the Indian Regional Navigational Satellite System, and the like. Alternatively, the location information / data can be determined by triangulating the user computing entity 10 position in connection with various other systems, including cellular towers, Wi-Fi access points, and the like. Similarly, the user computing entity 10 can include indoor positioning aspects, such as a positioning module adapted to obtain, for example, latitude, longitude, altitude, geocode, heading, orientation, direction, speed, time, date, and / or various other information / data. Some of these indoor aspects can use various positioning or location technologies, including RFID tags, indoor beacons or transmitters, Wi-Fi access points, cellular towers, nearby computing devices (e.g., smartphones, laptops), and the like. For example, such technologies can include iBeacon, Gimbal Proximity Beacon, BLE transmitters, Near Field Communication (NFC) transmitters, and the like. These indoor positioning aspects can be used in a variety of settings to determine the location of a person or thing to within inches or centimeters.

[0083] The user computing entity 10 can also include a user interface device that includes one or more user input / output interfaces (e.g., a display 616 and / or speakers / speaker drivers coupled to the processing element 608, and a touchscreen, keyboard, mouse, and / or microphone coupled to the processing element 608). For example, a user output interface can be configured to provide applications, browsers, user interfaces, interfaces, control panels, screens, webpages, pages, and / or like words used herein to cause display or audible presentation of information / data and to interact therewith via one or more user input interfaces that can be interchangeably executed on the computing entity 10 and / or accessed via the user computing entity. The user input interface can include any of a number of devices allowing user computing entity 10 to receive data, such as a keypad 618 (hard or soft), touch display, voice / speech or motion interfaces, scanners, readers or other input devices. In embodiments including a keypad 618, the keypad 618 can include (or cause display of) the conventional numeric (0-9) and related keys (#, *), and other keys used for operating the user computing entity 10, and can include a full alphanumeric keypad or set of keys that can be activated to provide a full set of alphanumeric keys. In addition to providing input, the user input interface can be used, for example, to activate or deactivate certain functions, such as screen savers and / or sleep modes. Through these input devices, the user computing entity 10 can receive information / data, user interactions / inputs, and the like.

[0084] The user computing entity 10 can also include volatile memory or storage 622 and / or non-volatile memory or storage 624, which can be embedded and / or can be removable. For example, the non-volatile memory can be ROM, PROM, EPROM, EEPROM, flash memory, MMCs, SD memory cards, Memory Sticks, CBRAM, PRAM, FeRAM, RRAM, SONOS, racetrack memory, and the like. The volatile memory can be RAM, DRAM, SRAM, FPM DRAM, EDO DRAM, SDRAM, DDR SDRAM, DDR2 SDRAM, DDR3 SDRAM, RDRAM, RIMM, DIMM, SIMM, VRAM, cache memory, register memory, and the like. The volatile and non-volatile storage or memory can store databases, database instances, database management system entities, data, applications, programs, program modules, scripts, source code, object code, byte code, compiled code, interpreted code, machine code, executable instructions, and the like to implement the functionality of the user computing entity 10.

[0085] In example embodiments, the user computing entity 10 can communicate with other user computing entities 10 and / or system computing entities 20.

[0086] Example system computing entity

[0087] Figure 7 A schematic diagram of a system computing entity 20 according to one embodiment of the present invention is provided. As described above, the system computing entity 20 may be configured to act as an intermediary between the controller 30 of the quantum computer 110 and one or more user computing entities 10. Generally, the terms system computing entity, computing entity, entity, device, system, and / or similar terms used interchangeably herein may refer to, for example, one or more computers, computing entities, desktop computers, mobile phones, tablet computers, phablets, laptops, distributed systems, articles / devices, terminals, servers or server networks, blade servers, gateways, switches, processing devices, processing entities, relays, routers, network access points, base stations, etc., and / or any combination of devices or entities suitable for performing the functions, operations, and / or processes described herein. Such functions, operations, and / or processes may include, for example, transmitting, receiving, operating, processing, displaying, storing, determining, creating / generating, monitoring, evaluating, comparing, and / or similar terms used interchangeably herein. In one embodiment, these functions, operations, and / or processes may be performed on data, content, information, and / or similar terms used interchangeably herein.

[0088] like Figure 7 As shown, in one embodiment, system computing entity 20 may include or communicate with one or more processing elements 705 (also referred to herein as processors, processing circuitry, and / or similar interchangeable terms) that communicate with other elements within system computing entity 20 via, for example, a bus. It should be understood that processing element 705 may be embodied in a variety of different ways. For example, processing element 705 may be embodied as one or more complex programmable logic devices (CPLDs), microprocessors, multi-core processors, coprocessor entities, application-specific instruction set processors (ASIPs), and / or controllers. Furthermore, processing element 705 may be embodied as one or more other processing devices or circuitry. The term "circuitry" may refer to a completely hardware implementation or a combination of hardware and computer program products. Thus, processing element 705 may be embodied as an integrated circuit, application-specific integrated circuit (ASIC), field-programmable gate array (FPGA), programmable logic array (PLA), hardware accelerator, other circuitry, etc. It should be understood that processing element 705 may be configured for a particular purpose or configured to execute instructions stored in volatile or non-volatile media or otherwise accessible to processing element 705. Therefore, whether configured by hardware, computer program products, or a combination thereof, when configured accordingly, the processing element 705 can be able to perform steps or operations according to embodiments of the present invention.

[0089] In one embodiment, the system computing entity 20 can also include or be in communication with non-volatile media (also referred to herein as non-volatile storage, memory, memory storage, memory circuitry, and / or similar terms used interchangeably). In one embodiment, the non-volatile storage or memory can include one or more non-volatile storage or memory media 710 as described above, such as a hard disk, ROM, PROM, EPROM, EEPROM, flash memory, MMC, SD memory card, Memory Stick, CBRAM, PRAM, FeRAM, RRAM, SONOS, racetrack memory, etc. As will be recognized, the non-volatile storage or memory media can store databases, database instances, database management system entities, data, applications, programs, program modules, scripts, source code, object code, byte code, compiled code, interpreted code, machine code, executable instructions, etc. The terms database, database instance, database management system entity, and / or similar terms used herein interchangeably can refer to a structured collection of records or information / data stored in a computer-readable storage medium, such as via a relational database, hierarchical database, and / or network database.

[0090] In one embodiment, the system computing entity 20 can also include or be in communication with volatile media (also referred to herein as non-volatile storage, memory, memory storage, memory circuitry, and / or similar terms used interchangeably). In one embodiment, the volatile storage or memory can also include one or more volatile storage or memory media 715 as described above, such as RAM, DRAM, SRAM, FPMDRAM, EDO DRAM, SDRAM, DDR SDRAM, DDR2 SDRAM, DDR3 SDRAM, RDRAM, RIMM, DIMM, SIMM, VRAM, cache memory, register memory, etc. As will be recognized, the volatile storage or memory media can be used to store at least portions of databases, database instances, database management system entities, data, applications, programs, program modules, scripts, source code, object code, byte code, compiled code, interpreted code, machine code, executable instructions, etc. executed by, for example, the processing element 705. Thus, databases, database instances, database management system entities, data, applications, programs, program modules, scripts, source code, object code, byte code, compiled code, interpreted code, machine code, executable instructions, etc. can be used to control certain aspects of the operation of the system computing entity 20 with the help of the processing element 705 and operating system.

[0091] As noted, in one embodiment, the system computing entity 20 can also include one or more networks and / or communication interfaces 720 for communicating with various computing entities, such as by transmitting data, content, information and / or similar terms used herein interchangeably that can be transmitted, received, operated on, processed, displayed, stored, etc. For example, the system computing entity 20 can communicate with the communication interfaces of the computing entity or one or more user computing entities 10, the controller 30, etc.

[0092] As noted, in one embodiment, the system computing entity 20 can also include one or more networks and / or communication interfaces 720 for communicating with various computing entities, such as by transmitting data, content, information, and / or similar terms used herein interchangeably that can be transmitted, received, operated on, processed, displayed, stored, etc. Such communication can be performed using wired data transmission protocols, such as fiber distributed data interface (FDDI), digital user line (DSL), Ethernet, asynchronous transfer mode (ATM), frame relay, data over cable service interface specification (DOCSIS), or any other wired transmission protocol. Similarly, the system computing entity 20 can be configured to communicate via wireless external communication networks using any of a variety of protocols, such as general packet radio service (GPRS), universal mobile telecommunications system (UMTS), code division multiple access 2000 (CDMA2000), CDMA2000 IX (lxRTT), wideband code division multiple access (WCDMA), global system for mobile communications (GSM), enhanced data rates for GSM evolution (EDGE), time division-synchronous code division multiple access (TD-SCDMA), long term evolution (LTE), evolved universal terrestrial radio access network (E-UTRAN), evolution-data optimized (EVDO), high-speed packet access (HSPA), high-speed downlink packet access (HSDPA), IEEE 802.11 (Wi-Fi), Wi-Fi Direct, 802.16 (WiMAX), ultra-wideband (UWB), infrared (IR) protocols, near-field communication (NFC) protocols, Wibree, Bluetooth protocols, wireless universal serial bus (USB) protocols, and / or any other wireless protocol. The system computing entity 20 can use such protocols and standards to communicate using border gateway protocol (BGP), dynamic host configuration protocol (DHCP), domain name system (DNS), file transfer protocol (FTP), hypertext transfer protocol (HTTP), HTTP over TLS / SSL / Secure, internet message access protocol (IMAP), network time protocol (NTP), simple mail transfer protocol (SMTP), remote login, transport layer security (TLS), secure sockets layer (SSL), internet protocol (IP), transmission control protocol (TCP), user datagram protocol (UDP), datagram congestion control protocol (DCCP), stream control transmission protocol (SCTP), hypertext markup language (HTML), etc.

[0093] It should be appreciated that one or more of the components of the system computing entity 20 can be located remotely from the other system computing entity 20 components, such as in a distributed system. Also, one or more of these components can be combined, and additional components performing functions described herein can be included in the system computing entity 20. Thus, the system computing entity 20 can be adapted to accommodate a variety of needs and circumstances.

[0094] Example controller

[0095] like Figure 8 As shown, in various embodiments, controller 30 may include various controller elements, including processing element 805, memory 810, driver controller element 815, communication interface 820, analog-to-digital converter element 825, etc. For example, processing element 805 may include a programmable logic device (CPLD), microprocessor, coprocessor entity, application-specific instruction set processor (ASIP), integrated circuit, application-specific integrated circuit (ASIC), field-programmable gate array (FPGA), programmable logic array (PLA), hardware accelerator, other processing devices and / or circuits, etc., and / or controllers. The term "circuit" may refer to a completely hardware implementation or a combination of hardware and computer program products. In an exemplary embodiment, processing element 805 of controller 30 includes a clock and / or communicates with a clock. For example, memory 810 may include non-transitory memory such as volatile and / or non-volatile memory, such as one or more of the following: hard disk, ROM, PROM, EPROM, EEPROM, flash memory, MMC, SD memory card, memory stick, CBRAM, PRAM, FeRAM, RRAM, SONOS, track memory, RAM, DRAM, SRAM, FPMDRAM, EDO DRAM, SDRAM, DDR SDRAM, DDR2 SDRAM, DDR3 SDRAM, RDRAM, RIMM, DIMM, SIMM, VRAM, cache memory, register memory, etc. In various embodiments, memory 810 may store qubit records corresponding to qubits of a quantum computer (e.g., in a qubit record data store, qubit record database, qubit record table, etc.), calibration table, executable queue, computer program code (e.g., one or more computer languages, dedicated controller languages, etc.). In an exemplary embodiment, execution of at least a portion of the computer program code stored in memory 810 (e.g., via processing element 805) causes controller 30 to perform one or more steps, operations, processes, programs, etc., as described herein for tracking the phase of a quantum object within a quantum system and resulting in the adjustment of the phase of one or more manipulation sources and / or signals generated therefrom.

[0096] In various embodiments, the driver controller elements 815 can include one or more driver and / or controller elements each configured to control one or more drivers. In various embodiments, the driver controller elements 815 can include drivers and / or driver controllers. For example, the driver controllers can be configured to operate one or more corresponding drivers in accordance with executable instructions, commands, etc. scheduled and executed by the controller 30 (e.g., by the processing elements 805). In various embodiments, the driver controller elements 815 can enable the controller 30 to operate the steering source 64 and / or modify the operation of the steering source 64 in order to control the phase of the signals generated by the steering source 64. In various embodiments, the drivers can be laser drivers; vacuum component drivers; drivers for controlling current and / or voltage applied to direct current (DC), radio frequency (RF), trapping / transmission and / or other electrodes for holding and / or controlling ion trapping potentials of the ion trap 50; cryogenic and / or vacuum system component drivers; etc. In various embodiments, the controller 30 includes means for transmitting and / or receiving signals from one or more optical receiver components, such as cameras, MEM cameras, CCD cameras, photodiodes, photomultiplier tubes, etc. For example, the controller 30 can include one or more analog-to-digital converter elements 825 configured to receive signals from one or more optical receiver components, calibration sensors 62, etc. In various embodiments, the controller 30 can include a communication interface 820 for connecting and / or communicating with the system computing entity 20. For example, the controller 30 can include a communication interface 820 for receiving executable instructions, command sets, etc. from the system computing entity 20, and providing outputs received from the quantum computer 110 (e.g., from the optical collection system) and / or providing results of processing the outputs to the system computing entity 20. In various embodiments, the system computing entity 20 and the controller 30 can communicate via direct wired and / or wireless connections and / or one or more wired and / or wireless networks.

[0097] Conclusion

[0098] Many modifications and other embodiments of the present invention set forth herein will come to mind to one skilled in the art to which the invention pertains having the benefit of the teachings presented in the foregoing description and the associated drawings. Therefore, it is to be understood that the invention is not to be limited to the specific embodiments disclosed and that modifications and other embodiments are intended to be included within the scope of the appended claims. Although specific terms are employed herein, they are used in a generic and descriptive sense only and not for purposes of limitation.

Claims

1. A method comprising: identifying, by a controller corresponding to a quantum system, a phase update trigger for a particular quantum object of the quantum system, the phase update trigger corresponding to an interaction time; determining, by the controller in response to identifying the phase update trigger, a position and transport effect on a phase of the particular quantum object based on one or more positions of the particular quantum object and one or more transport operations performed on the particular quantum object between a first time and the interaction time, wherein an immediately preceding phase update of the particular quantum object occurred at the first time, and each of the one or more transport operations includes a transport of the particular quantum object from a respective first region to a respective second region of an ion trap of the quantum system; determining, by the controller, a quantum operation effect on the phase of the particular quantum object based on any quantum operations applied to the particular quantum object between the first time and the interaction time; determining, by the controller, an interaction time phase of the particular quantum object based on the position and transport effect, the quantum operation effect, and the interaction time; and causing, by the controller, a phase of one or more signals (a) to be generated by one or more steering sources and (b) to correspond to the phase update trigger to be adjusted, such that the phase of the one or more signals corresponds to the interaction time phase of the particular quantum object at the interaction time.

2. The method of claim 1, wherein the one or more signals are incident on the particular quantum object at the interaction time.

3. The method of claim 1, wherein the one or more steering sources include at least one of (a) one or more lasers or (b) one or more voltage sources.

4. The method of claim 1, wherein the quantum operation effect corresponds to a Stark shift.

5. The method of claim 1, wherein the quantum system is part of a trapped-ion quantum computer, and the particular quantum object is a qubit of the trapped-ion quantum computer.

6. The method of claim 1, wherein the phase of a signal of the one or more signals corresponds to the interaction time phase of the particular quantum object when an absolute value of a difference between the phase of the signal and the interaction time phase of the particular quantum object satisfies a phase difference threshold requirement.

7. The method of claim 6, wherein the absolute value of the difference between the phase of the signal and the interaction time phase satisfies the phase difference threshold requirement when the absolute value of the difference between the phase of the signal and the interaction time phase is less than a set phase difference threshold.

8. The method of claim 1, wherein the phase update trigger is identified by determining that an application of the one or more signals to the particular quantum object is scheduled to occur at the interaction time. ​ 9. The method of claim 1, wherein identifying the phase update trigger corresponding to the particular quantum object, determining the position and transport effect of the phase of the particular quantum object, determining the quantum operation effect on the phase of the particular quantum object, and causing the adjustment of the phase of the one or more signals are performed in real-time or near real-time with respect to each other.

10. The method of claim 1, wherein the position and transport effect corresponds to a phase change due to a change in an effective frequency of the particular quantum object based on one or more positions of the particular quantum object and a transport of the particular quantum object through the one or more positions between the first time and the interaction time.

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