Calculation device

Abstract

To provide a calculation device that can improve characteristics.SOLUTION: A calculation device includes an element part, a first control member, and a control unit. The element part includes a first quantum bit including a first loop including a plurality of first Josephson junctions, and a second quantum bit including a second loop including a plurality of second Josephson junctions. The second quantum bit can be coupled to the first quantum bit. The control unit can cause the first control member to execute a first operation. In the first operation, the control unit causes the first control member to apply a pulse wave including a DC component to the first loop, while applying a first signal wave including a first AC component to the first loop.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] FIELD OF THE DISCLOSURE Embodiments of the present invention relate to a computing device. [Background technology]

[0002] For example, electronic circuits including a plurality of nonlinear elements are used in computing devices, and improved performance is desired in electronic circuits and computing devices. [Prior art documents] [Non-patent literature]

[0003] [Non-Patent Document 1] H. Chono et al., Phys. Rev. Res. 4, 043054 (2022). Summary of the Invention [Problem to be solved by the invention]

[0004] SUMMARY OF THE PRESENT EMBODIMENTS Embodiments of the present invention provide a computing device that can have improved performance. [Means for solving the problem]

[0005] According to an embodiment of the present invention, a computing device includes an element unit, a first control member, and a control unit. The element unit includes a first quantum bit including a first loop including a plurality of first Josephson junctions, and a second quantum bit including a second loop including a plurality of second Josephson junctions. The second quantum bit is capable of being coupled to the first quantum bit. The control unit is capable of causing the first control member to perform a first operation. In the first operation, the control unit causes the first control member to apply a first signal wave including a first AC component to the first loop, while applying a pulse wave including a DC component to the first loop. [Brief description of the drawings]

[0006] [Figure 1] FIG. 1 is a schematic diagram illustrating a computing device according to the first embodiment. [Diagram 2] FIG. 2 is a schematic diagram illustrating a computing device according to the first embodiment. [Diagram 3] FIG. 3 is a schematic diagram illustrating a computing device according to the second embodiment. [Figure 4] FIG. 4 is a schematic diagram illustrating the operation of the computing device according to the second embodiment. [Diagram 5] FIG. 5 is a schematic diagram illustrating the operation of the computing device according to the embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0007] Hereinafter, an embodiment of the present invention will be described with reference to the drawings. The drawings are schematic or conceptual, and the relationship between the thickness and width of each part, the size ratio between parts, etc. are not necessarily the same as those in reality. Even when the same part is shown, the dimensions and ratios of each part may be different depending on the drawing. In this specification and each drawing, elements similar to those described above with reference to the previous drawings are given the same reference numerals and detailed descriptions thereof will be omitted as appropriate.

[0008] (First embodiment) FIG. 1 is a schematic diagram illustrating a computing device according to the first embodiment. As shown in FIG. 1, a computing device 110 according to the embodiment includes an element unit 10E, a first control member 71, and a control unit .

[0009] The element unit 10E includes a first quantum bit 11Q and a second quantum bit 12Q. The first quantum bit 11Q includes a first loop 11L. The first loop 11L includes a plurality of first Josephson junctions 11. For example, the first loop 11L includes two first Josephson junctions 11. In this example, the first quantum bit 11Q includes a plurality of first loops 11L. Two of the plurality of first loops 11L are connected to each other.

[0010] In this example, the first quantum bit 11Q further includes a first capacitor 11C. The first capacitor 11C is connected in parallel with the first loop 11L.

[0011] The second quantum bit 12Q includes a second loop 12L. The second loop 12L includes a plurality of second Josephson junctions 12. For example, the second loop 12L includes two second Josephson junctions 12. In this example, the second quantum bit 12Q includes a plurality of second loops 12L. Two of the plurality of second loops 12L are connected to each other.

[0012] In this example, the second quantum bit 12Q further includes a second capacitor 12C. The second capacitor 12C is connected in parallel with the second loop 12L.

[0013] The second qubit 12Q can be coupled to the first qubit 11Q. For example, the second qubit 12Q is coupled to the first qubit 11Q via a capacitor 15. The coupling can include, for example, capacitive coupling. The coupling can include, for example, any electromagnetic coupling.

[0014] The first control member 71 may be provided, for example, near the first loop 11L. The computing device 110 may include a second control member 72. The second control member 72 may be provided near the second loop 12L. These control members are, for example, conductive members. An electrical signal is supplied to these conductive members from the control unit 70. This causes a magnetic field to be generated from the conductive members. This magnetic field controls the magnetic flux in the loop.

[0015] The control unit 70 can cause the first control member 71 to execute a first operation OP1. In the first operation OP1, the control unit 70 causes the first control member 71 to apply a first signal wave AS1 to the first loop 11L while applying a pulse wave PS1 to the first loop 11L. The first signal wave AS1 includes a first AC component. The pulse wave PS1 is a pulse wave including a DC component.

[0016] For example, the magnetic flux in the first loop 11L is modulated by the first signal wave AS1 including a first AC component at the frequency of the first AC component. The magnetic flux in the first loop 11L is controlled according to the DC component of the pulse wave PS1 by the first signal wave AS1. By such a first operation OP1, for example, a two-qubit gate operation can be performed at high speed.

[0017] For example, when performing a two-qubit gate operation using microwaves, an AC Stark shift may occur. The AC Stark shift causes the resonance frequency of the qubit to shift from its initial value. This may increase the time required for a two-qubit gate operation with high gate fidelity.

[0018] In the embodiment, a first signal wave AS1 including an AC component is applied to the first loop 11L, while a pulse wave PS1 including a DC component is applied to the first loop 11L. The pulse wave PS1 compensates for the shift in the resonant frequency of the first quantum bit 11Q. The pulse wave PS1 is set, for example, so as to correspond to the shift in the resonant frequency of the first quantum bit 11Q caused by the AC Stark shift caused by the first signal wave AS1. This allows high-speed two-qubit gate operations to be performed. Two-qubit gate operations with high gate fidelity can be performed. According to the embodiment, a computing device capable of improving characteristics can be provided.

[0019] For example, the first quantum bit 11Q is a parametric oscillator (Kerr parametric oscillator, KPO). The first quantum bit 11Q oscillates by modulating the magnetic flux in the first loop 11L with a first parametric excitation frequency fp1. The first parametric excitation frequency fp1 is substantially twice the first characteristic frequency ω1 of the first quantum bit 11Q. The first characteristic frequency ω1 corresponds to a first resonant frequency of the first quantum bit 11Q when no signal from the outside world is applied to the first quantum bit 11Q. The magnetic flux in the first loop 11L is controlled by a first control member 71.

[0020] For example, the second quantum bit 12Q is a parametric oscillator (Kerr parametric oscillator, KPO). The second quantum bit 12Q oscillates by modulating the magnetic flux in the second loop 12L with a second parametric excitation frequency fp2. The second parametric excitation frequency fp2 is substantially twice the second characteristic frequency ω2 of the second quantum bit 12Q. The second characteristic frequency ω2 corresponds to a second resonant frequency of the second quantum bit 12Q when no signal from the outside world is applied to the second quantum bit 12Q. The magnetic flux in the second loop 12L is controlled by a second control member 72.

[0021] For example, the detuning is controlled by the pulse wave PS1. In the embodiment, the detuning of the first quantum bit 11Q corresponds to the difference between the resonant frequency after the first quantum bit 11Q is shifted by the AC Stark shift and ½ of the first parametric excitation frequency fp1.

[0022] For example, the frequency of the first AC component of the first signal wave AS1 may be the sum of the first characteristic frequency ω1 of the first quantum bit 11Q and the second characteristic frequency ω2 of the second quantum bit 12Q (ie, ω1+ω2).

[0023] For example, when the first characteristic frequency ω1 is lower than the second characteristic frequency ω2, the resonant frequency of the first quantum bit 11Q shifts from its initial value to a higher frequency due to the AC Stark shift caused by the first signal wave AS1. For example, the resonant frequency of the quantum bit shifts to a lower frequency due to the pulse wave PS1. This compensates for the AC Stark shift.

[0024] For example, when the first characteristic frequency ω1 is higher than the second characteristic frequency ω2, the resonant frequency of the first quantum bit 11Q shifts from its initial value to a lower frequency side due to the AC Stark shift caused by the first signal wave AS1. For example, the resonant frequency of the first quantum bit 11Q shifts to a higher frequency side due to the pulse wave PS1. This compensates for the AC Stark shift.

[0025] According to the embodiment, high-speed two-qubit gate operations can be performed. Two-qubit gate operations with high gate fidelity can be performed.

[0026] In an embodiment, for example, the second characteristic frequency ω2 may be higher than the first characteristic frequency ω1. This makes it easier to obtain high fidelity. In one example, the first characteristic frequency ω1 may be 9 GHz or more and 9.5 GHz or less. In one example, the second characteristic frequency ω2 may be 10 GHz or more and 10.5 GHz or less.

[0027] The control unit 70 executes a two-qubit gate in the first quantum bit 11Q and the second quantum bit 12Q by the above-mentioned first operation OP1.

[0028] For example, there is a first reference example in which the pulse wave PS1 is not applied and only the first signal wave AS1 is applied. In the two-qubit gate operation in the first reference example, the gate fidelity is 0.9871 when the gate time is 15 ns.

[0029] In contrast, in the embodiment, the pulse wave PS1 is applied together with the first signal wave AS1. In the two-qubit gate operation in this embodiment, the gate fidelity is 0.9964 when the gate time is 15 ns. Thus, in the embodiment, a higher gate fidelity is obtained compared to the first reference example. This corresponds to a shorter time required to obtain the same gate fidelity. According to the embodiment, high-speed two-qubit gate operation is possible.

[0030] FIG. 2 is a schematic diagram illustrating a computing device according to the first embodiment. 2 illustrates another first operation OP1 in the computing device 111 according to the embodiment. The configurations of the element unit 10E and the first control member 71 in the computing device 111 may be similar to those in the computing device 110. In another first operation OP1 in the computing device 111, the control unit 70 causes the first control member 71 to apply a first signal wave AS1 including a first AC component to the first loop 11L, apply a second signal wave AS2 including a second AC component to the first loop 11L, and apply a pulse wave PS1 including a DC component to the first loop 11L.

[0031] For example, the phase of the second AC component (second phase) is shifted from the phase of the first AC component (first phase). The difference between the second phase and the first phase may be, for example, 80 degrees or more and 110 degrees or less. For example, the difference between the second phase and the first phase is, for example, 90 degrees. For example, the frequency of the second AC component may be substantially the same as the frequency of the first AC component.

[0032] By applying such a phase-shifted second signal wave AS2, even faster two-qubit gate operation can be obtained. For example, when the second signal wave AS2 is further used, the gate fidelity is 0.9984 when the gate time is 15 ns in two-qubit gate operation. Even higher gate fidelity can be obtained. The characteristics can be improved.

[0033] The application of the phase-shifted second signal wave AS2 corresponds, for example, to a differential signal of the first signal wave AS1 for gating.

[0034] An operation similar to the first operation OP1 described with reference to FIG. 1 and FIG. 2 may be applied to the second quantum bit 12Q. For example, as shown in FIG. 1 and FIG. 2, a second control member 72 may be further provided. The control unit 70 may be capable of causing the second control member 72 to perform a second operation. In the second operation, the control unit causes the second control member 72 to apply a second quantum bit signal wave including a second quantum bit AC component to the second loop 12L while applying a second quantum bit pulse wave including a second quantum bit DC component to the second loop 12L. A high-speed two-qubit gate operation can be performed in the first quantum bit 11Q and the second quantum bit 12Q. A two-qubit gate operation with high gate fidelity can be performed.

[0035] Second embodiment FIG. 3 is a schematic diagram illustrating a computing device according to the second embodiment. 3, the computing device 120 according to the embodiment also includes an element unit 10E, a first control member 71, and a control unit 70. The configurations of the element unit 10E and the first control member 71 in the computing device 120 may be similar to those in the computing device 110 or the computing device 111.

[0036] In the computing device 120, in a first operation OP1, the control unit 70 causes the first control member 71 to apply a first signal wave AS1 including a first AC component to the first loop 11L. The frequency of the first AC component changes over time. This compensates for, for example, a shift in the resonant frequency of the first quantum bit 11Q caused by the AC Stark shift caused by the first signal wave AS1. This allows high-speed two-qubit gate operations to be performed. According to the embodiment, a computing device capable of improving characteristics can be provided.

[0037] FIG. 4 is a schematic diagram illustrating the operation of the computing device according to the second embodiment. Fig. 4 illustrates an example of a change in the frequency of the first AC component. The horizontal axis of Fig. 4 represents time tm. The vertical axis represents the frequency of the first AC component.

[0038] At a first time t1 at the start of the first operation OP1, the first AC component has a first time frequency f1. At a second time t2 after the first time t1 in the first operation OP1, the first AC component has a second time frequency f2. In this example, the second time frequency f2 is higher than the first time frequency f1.

[0039] 4, at a third time t3 after the second time t2 in the first operation OP1, the first AC component has a third time frequency f3. The third time frequency f3 is lower than the second time frequency f2. The first time frequency f1, the second time frequency f2, and the third time frequency f3 may be angular frequencies.

[0040] Thus, in the first operation OP1, the frequency of the first AC component may increase and then decrease.In an embodiment, in the first operation OP1, the frequency of the first AC component may decrease and then increase.

[0041] In one example, the first time frequency f1 may correspond to the sum of a first characteristic frequency ω1 of the first quantum bit 11Q and a second characteristic frequency ω2 of the second quantum bit 12Q.

[0042] For example, a first difference (absolute value) between the sum of the first characteristic frequency ω1 of the first quantum bit 11Q and the second characteristic frequency ω2 of the second quantum bit 12Q and the first time frequency f1 is smaller than a second difference (absolute value) between the sum and the second time frequency f2.

[0043] The first characteristic frequency ω1 corresponds to, for example, the first resonant frequency of first quantum bit 11Q when no external signal is applied to first quantum bit 11Q. The second characteristic frequency ω2 corresponds to the second resonant frequency of second quantum bit 12Q when no external signal is applied to second quantum bit 12Q.

[0044] When the first characteristic frequency ω1 is higher than the second characteristic frequency ω2, the resonant frequency of the first quantum bit 11Q shifts from its initial value to a higher frequency side due to the AC Stark shift caused by the first signal wave AS1. When the first characteristic frequency ω1 is lower than the second characteristic frequency ω2, the resonant frequency of the first quantum bit 11Q shifts from its initial value to a lower frequency side due to the AC Stark shift caused by the first signal wave AS1. Under a first condition in which the first characteristic frequency ω1 is higher than the second characteristic frequency ω2, the second time frequency f2 is set higher than the first time frequency f1. Under a second condition in which the first characteristic frequency ω1 is lower than the second characteristic frequency ω2, the second time frequency f2 is set lower than the first time frequency f1.

[0045] In the above first condition, the third time frequency f3 is lower than the second time frequency f2. In the above second condition, the third time frequency f3 is higher than the second time frequency f2.

[0046] In the computing device 120, an operation similar to the first operation OP1 described above may be applied to the second quantum bit 12Q. The control unit 70 may be capable of causing the second control member 72 to perform a second operation. In the second operation, the control unit 70 causes the second control member 72 to apply a second quantum bit signal wave including a second quantum bit AC component to the second loop 12L. The frequency of the second quantum bit AC component varies over time. A high-speed two-qubit gate can be performed in the first quantum bit 11Q and the second quantum bit 12Q. A two-qubit gate with high gate fidelity can be performed.

[0047] In the above first operation OP1, the first parametric excitation frequency fp1 may be modulated.

[0048] FIG. 5 is a schematic diagram illustrating the operation of the computing device according to the embodiment. As shown in FIG. 5, before the first operation OP1, the first parametric excitation frequency fp1 is at a frequency fa1. The frequency fa1 is substantially twice the first characteristic frequency ω1 of the first quantum bit 11Q. The first operation OP1 changes the first parametric excitation frequency fp1 to a frequency fa2. After the first operation OP1, the first parametric excitation frequency fp1 is set to a frequency fa3. The frequency fa3 is substantially twice the first characteristic frequency ω1.

[0049] The embodiments may include the following technical solutions. (Technical proposal 1) a first qubit including a first loop including a plurality of first Josephson junctions; a second qubit including a second loop including a second plurality of Josephson junctions, the second qubit being couplable with the first qubit; An element portion including: A first control member; a control unit capable of causing the first control member to perform a first operation; Equipped with In the first operation, the control unit causes the first control member to apply a first signal wave including a first AC component to the first loop while applying a pulse wave including a DC component to the first loop.

[0050] (Technical proposal 2) the first signal wave causes the magnetic flux in the first loop to be modulated with a frequency of the first AC component; The computing device described in technical solution 1, wherein the magnetic flux in the first loop is controlled according to the DC component by the pulse wave.

[0051] (Technical proposal 3) The computing device of technical solution 1, wherein the frequency of the first AC component is the sum of a first characteristic frequency of the first quantum bit and a second characteristic frequency of the second quantum bit.

[0052] (Technical proposal 4) the first characteristic frequency corresponds to a first resonant frequency of the first quantum bit when no external signal is applied to the first quantum bit; The computing device according to technical solution 3, wherein the second characteristic frequency corresponds to a second resonant frequency of the second quantum bit when no external signal is applied to the second quantum bit.

[0053] (Technical proposal 5) The computing device according to any one of Technical Solutions 1 to 4, wherein the control unit executes a two-qubit gate on the first quantum bit and the second quantum bit by the first operation.

[0054] (Technical proposal 6) In the first operation, the control unit causes the first control member to apply the first signal wave including the first AC component to the first loop, while applying a second signal wave including a second AC component to the first loop, and while applying the pulse wave including the DC component to the first loop. The computing device described in Technical Proposal 1.

[0055] (Technical proposal 7) The calculation device according to technical proposal 6, wherein a difference between the second phase of the second AC component and the first phase of the first AC component is greater than or equal to 80 degrees and less than or equal to 110 degrees.

[0056] (Technical proposal 8) The computing device according to any one of Technical Schemes 1 to 7, wherein the first quantum bit and the second quantum bit are parametric oscillators.

[0057] (Technical proposal 9) a first qubit including a first loop including a plurality of first Josephson junctions; a second qubit including a second loop including a second plurality of Josephson junctions, the second qubit being couplable with the first qubit; An element portion including: A first control member; a control unit capable of causing the first control member to perform a first operation; Equipped with In the first operation, the control unit causes the first control member to apply a first signal wave including a first AC component to the first loop; The frequency of the first AC component varies over time.

[0058] (Technical proposal 10) At a first time when the first operation starts, the first AC component has a first time frequency; At a second time after the first time in the first operation, the first AC component has a second time frequency; Under a first condition in which a first characteristic frequency of the first quantum bit is higher than a second characteristic frequency of the second quantum bit, the second time frequency is higher than the first time frequency; The calculation device of technical proposal 9, wherein under a second condition in which the first characteristic frequency is lower than the second characteristic frequency, the second time-of-day frequency is lower than the first time-of-day frequency.

[0059] (Technical proposal 11) At a third time point after the second time point in the first operation, the first AC component has a third time frequency; Under the first condition, the third time frequency is lower than the second time frequency, The calculation device according to technical solution 10, wherein in the second condition, the third time frequency is higher than the second time frequency.

[0060] (Technical proposal 12) The computing device according to Technical Solution 10 or 11, wherein the first time frequency corresponds to the sum of a first characteristic frequency of the first quantum bit and a second characteristic frequency of the second quantum bit.

[0061] (Technical proposal 13) The computing device according to technical proposal 10 or 11, wherein a first difference between the sum of the first characteristic frequency of the first quantum bit and the second characteristic frequency of the second quantum bit and the first time frequency is smaller than a second difference between the sum and the second time frequency.

[0062] (Technical proposal 14) the first characteristic frequency corresponds to a first resonant frequency of the first quantum bit when no external signal is applied to the first quantum bit; The computing device according to technical solution 13, wherein the second characteristic frequency corresponds to a second resonant frequency of the second quantum bit when no external signal is applied to the second quantum bit.

[0063] (Technical proposal 15) The computing device according to any one of Technical Schemes 1 to 14, wherein the first quantum bit further includes a first capacitor connected in parallel with the first loop.

[0064] (Technical proposal 16) the first quantum bit includes a plurality of the first loops; Two of the first loops are connected to each other; The computing device according to any one of Technical Solutions 1 to 15, wherein the control unit causes the first control member to execute the first operation for each of the plurality of first loops.

[0065] (Technical proposal 17) the second quantum bit includes a plurality of the second loops; The computing device described in technical proposal 16, wherein two of the plurality of second loops are connected to each other.

[0066] (Technical proposal 18) Further comprising a second control member; The control unit is capable of causing the second control member to perform a second operation, In the second operation, the control unit causes the second control member to apply a second quantum bit signal wave including a second quantum bit AC component to the second loop while applying a second quantum bit pulse wave including a second quantum bit DC component to the second loop. The computing device described in Technical Proposal 1.

[0067] (Technical proposal 19) Further comprising a second control member; The control unit is capable of causing the second control member to perform a second operation, In the second operation, the control unit causes the second control member to apply a second quantum bit signal wave including a second quantum bit AC component to the second loop; The computing device described in Technical Proposal 9, wherein the frequency of the second quantum bit AC component varies over time.

[0068] (Technical proposal 20) the first quantum bit is capable of oscillating by modulating a magnetic flux in the first loop with a first parametric excitation frequency; the second quantum bit is capable of oscillating by modulating a magnetic flux in the second loop with a second parametric excitation frequency; 20. The computing device according to claim 1, wherein the control unit is capable of changing the first parametric excitation frequency in the first operation.

[0069] According to the embodiment, it is possible to provide an electronic circuit and a computing device that can improve the performance.

[0070] The above describes the embodiment of the present invention with reference to examples. However, the present invention is not limited to these examples. For example, the specific configuration of each element included in the computing device, such as the element unit, quantum bit, control member, and control unit, is included in the scope of the present invention as long as a person skilled in the art can implement the present invention in the same way by appropriately selecting from the known range and obtain the same effect.

[0071] Any combination of two or more elements of each example, within the scope of technical feasibility, is also included within the scope of the present invention as long as it includes the gist of the present invention.

[0072] All computing devices that can be implemented by a person skilled in the art by appropriately modifying the design of the computing device described above as an embodiment of the present invention are within the scope of the present invention as long as they include the gist of the present invention.

[0073] Within the scope of the concept of the present invention, a person skilled in the art may conceive of various modifications and alterations, and it is understood that these modifications and alterations also fall within the scope of the present invention.

[0074] Although some embodiments of the present invention have been described, these embodiments are presented as examples and are not intended to limit the scope of the invention. These novel embodiments can be implemented in various other forms, and various omissions, substitutions, and modifications can be made without departing from the spirit of the invention. These embodiments and their modifications are included in the scope and spirit of the invention, and are included in the scope of the invention and its equivalents described in the claims. [Explanation of symbols]

[0075] 10E: element section; 11, 12: first and second Josephson junctions; 11C, 12C: first and second capacitors; 11L, 12L: first and second loops; 11Q, 12Q: first and second quantum bits; 15: capacitor; 70: control section; 71, 72: first and second control members; 110, 111, 120: calculation devices; AS1, AS2: first and second signal waves; OP1: first operation; PS1: pulse wave; f1 to f3: first to third time frequencies; fa1 to fa3, fb1 to fb3: frequencies; fp1, fp2: first and second parametric excitation frequencies; t1 to t3: first to third times; tm: time

Claims

1. a first qubit including a first loop including a plurality of first Josephson junctions; a second qubit including a second loop including a second plurality of Josephson junctions, the second qubit being couplable with the first qubit; An element portion including: A first control member; a control unit capable of causing the first control member to perform a first operation; Equipped with In the first operation, the control unit causes the first control member to apply a first signal wave including a first AC component to the first loop while applying a pulse wave including a DC component to the first loop.

2. the first signal wave causes the magnetic flux in the first loop to be modulated with a frequency of the first AC component; The computing device of claim 1 , wherein the pulse wave controls the magnetic flux in the first loop in response to the DC component.

3. 2. The computing device of claim 1, wherein the frequency of the first AC component is the sum of a first characteristic frequency of the first quantum bit and a second characteristic frequency of the second quantum bit.

4. The computing device of claim 1 , wherein the control unit executes a two-qubit gate on the first quantum bit and the second quantum bit by the first operation.

5. 2. The computing device of claim 1, wherein in the first operation, the control unit causes the first control member to apply the first signal wave including the first AC component to the first loop, apply a second signal wave including a second AC component to the first loop, and apply the pulse wave including the DC component to the first loop.

6. The computing device of claim 5 , wherein a difference between the second phase of the second AC component and the first phase of the first AC component is equal to or greater than 80 degrees and equal to or less than 110 degrees.

7. a first qubit including a first loop including a plurality of first Josephson junctions; a second qubit including a second loop including a second plurality of Josephson junctions, the second qubit being couplable with the first qubit; An element portion including: A first control member; a control unit capable of causing the first control member to perform a first operation; Equipped with In the first operation, the control unit causes the first control member to apply a first signal wave including a first AC component to the first loop; The frequency of the first AC component varies over time.

8. At a first time when the first operation starts, the first AC component has a first time frequency; At a second time after the first time in the first operation, the first AC component has a second time frequency; Under a first condition in which a first characteristic frequency of the first quantum bit is higher than a second characteristic frequency of the second quantum bit, the second time frequency is higher than the first time frequency; The calculation device according to claim 7 , wherein in a second condition in which the first characteristic frequency is lower than the second characteristic frequency, the second time-of-day frequency is lower than the first time-of-day frequency.

9. At a third time point after the second time point in the first operation, the first AC component has a third time frequency; Under the first condition, the third time frequency is lower than the second time frequency, The computing device of claim 8 , wherein in the second condition, the third time frequency is higher than the second time frequency.

10. the first quantum bit is capable of oscillating by modulating a magnetic flux in the first loop with a first parametric excitation frequency; the second quantum bit is operable to oscillate by modulating a magnetic flux in the second loop with a second parametric excitation frequency; The computing device according to claim 1 , wherein the control unit is capable of changing the first parametric excitation frequency in the first operation.

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