Electronic circuit, computing device, and method for manufacturing electronic circuit

Abstract

To provide an electronic circuit capable of improving characteristics, a calculation device and a manufacturing method of the electronic circuit.SOLUTION: An electronic circuit includes a first nonlinear element, a second nonlinear element and a third nonlinear element. The first nonlinear element includes a first element Josephson junction provided in a first region of a first face including the first region and a second region. The second nonlinear element includes a second element Josephson junction provided in the second region. The third nonlinear element includes a Josephson junction circuit. At least a portion of the Josephson junction circuit is provided on a second face. The second face is along the first face while being separated from the first face in a first direction crossing the first face. The third nonlinear element can be coupled with the first nonlinear element. The third nonlinear element can be coupled with the second nonlinear element.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] FIELD OF THE INVENTION Embodiments of the present invention relate to electronic circuits, computing devices, and methods for manufacturing electronic circuits. [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] [Patent documents]

[0003] [Patent Document 1] US Patent Application Publication No. 2019 / 0214971 Summary of the Invention [Problem to be solved by the invention]

[0004] SUMMARY OF THE INVENTION Embodiments of the present invention provide electronic circuits, computing devices, and methods for manufacturing electronic circuits that can improve performance. [Means for solving the problem]

[0005] According to an embodiment of the present invention, an electronic circuit includes a first nonlinear element, a second nonlinear element, and a third nonlinear element. The first nonlinear element includes a first-element Josephson junction provided in a first region of a first surface including a first region and a second region. The second nonlinear element includes a second-element Josephson junction provided in the second region. The third nonlinear element includes a Josephson junction circuit. At least a portion of the Josephson junction circuit is provided on a second surface. The second surface is apart from the first surface in a first direction intersecting the first surface and extends along the first surface. The third nonlinear element is couplable with the first nonlinear element. The third nonlinear element is couplable with the second nonlinear element. [Brief explanation of the drawings]

[0006] [Figure 1] 1A and 1B are schematic plan views illustrating an electronic circuit and a computing device according to the first embodiment. [Figure 2] FIG. 2 is a schematic cross-sectional view illustrating the electronic circuit and the computing device according to the first embodiment. [Figure 3] FIG. 3 is a schematic diagram illustrating an electronic circuit and a computing device according to the first embodiment. [Figure 4] 4A and 4B are schematic cross-sectional views illustrating a part of the electronic circuit according to the first embodiment. [Figure 5] 5(a) to 5(e) are schematic cross-sectional views illustrating a part of the electronic circuit according to the first embodiment. [Figure 6] FIG. 6 is a schematic cross-sectional view illustrating the electronic circuit according to the first embodiment. [Figure 7] 7A and 7B are schematic plan views illustrating a part of the electronic circuit according to the first embodiment. [Figure 8] 8A and 8B are schematic plan views illustrating a part of the electronic circuit according to the first embodiment. [Figure 9] 9A and 9B are schematic plan views illustrating the electronic circuit according to the first embodiment. [Figure 10] 10A and 10B are schematic plan views illustrating the electronic circuit according to the first embodiment. [Figure 11] 11A and 11B are schematic plan views illustrating the electronic circuit according to the first embodiment. [Figure 12] 12A and 12B are schematic plan views illustrating the electronic circuit according to the first embodiment. [Figure 13] 13A and 13B are schematic plan views illustrating the electronic circuit according to the first embodiment. [Figure 14] 14A and 14B are schematic plan views illustrating the electronic circuit according to the first embodiment. [Figure 15]15A and 15B are schematic plan views illustrating the electronic circuit according to the first embodiment. [Figure 16] FIG. 16 is a schematic cross-sectional view illustrating the electronic circuit according to the first embodiment. [Figure 17] FIG. 17 is a graph illustrating the characteristics of the computing device according to the first embodiment. [Figure 18] FIG. 18 is a graph illustrating the characteristics of the computing device according to the first embodiment. [Figure 19] FIG. 19 is a graph illustrating the characteristics of the computing device according to the first embodiment. [Figure 20] FIG. 20 is a graph illustrating the characteristics of the computing device according to the first embodiment. [Figure 21] FIG. 21 is a graph illustrating the characteristics of the computing device according to the first embodiment. [Figure 22] FIG. 22 is a schematic plan view illustrating the electronic circuit according to the first embodiment. [Figure 23] 23A and 23B are schematic plan views illustrating the electronic circuit according to the second embodiment. [Figure 24] 24(a) and 24(b) are schematic plan views illustrating the electronic circuit according to the second embodiment. [Figure 25] 25(a) and 25(b) are schematic plan views illustrating the electronic circuit according to the second embodiment. [Figure 26] 26(a) and 26(b) are schematic plan views illustrating the electronic circuit according to the second embodiment. [Figure 27] 27(a) and 27(b) are schematic plan views illustrating the electronic circuit according to the second embodiment. [Figure 28] 28(a) and 28(b) are schematic plan views illustrating the electronic circuit according to the second embodiment. [Figure 29] 29(a) and 29(b) are schematic plan views illustrating the electronic circuit according to the second embodiment. [Figure 30]FIG. 30 is a schematic cross-sectional view illustrating an electronic circuit according to the second embodiment. [Figure 31] FIG. 31 is a schematic cross-sectional view illustrating an electronic circuit according to the second embodiment. [Figure 32] FIG. 32 is a schematic cross-sectional view illustrating an electronic circuit according to the second embodiment. [Figure 33] FIG. 33 is a schematic diagram illustrating an electronic circuit and a computing device according to the embodiment. [Figure 34] 34(a) to 34(i) are schematic cross-sectional views illustrating a method for manufacturing an electronic circuit according to the third embodiment. [Figure 35] 35(a) to 35(i) are schematic cross-sectional views illustrating a method for manufacturing an electronic circuit according to the third embodiment. DETAILED DESCRIPTION OF THE INVENTION

[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 may be different depending on the drawing. In this specification and in each drawing, elements similar to those previously described with reference to the previous drawings are designated by the same reference numerals, and detailed descriptions thereof will be omitted where appropriate.

[0008] (First embodiment) 1A and 1B are schematic plan views illustrating an electronic circuit and a computing device according to the first embodiment. FIG. 2 is a schematic cross-sectional view illustrating the electronic circuit and the computing device according to the first embodiment. Fig. 2 is a cross-sectional view corresponding to the A1-A2 line in Fig. 1(a) and Fig. 1(b). Fig. 2 conceptually illustrates the cross-sectional configuration, and the lengths in Fig. 2 do not necessarily match the lengths in Fig. 1(a) and Fig. 1(b).

[0009] 1(a), 1(b), and 2, an electronic circuit 110 according to the embodiment includes a first nonlinear element 50A, a second nonlinear element 50B, and a third nonlinear element 50C. The electronic circuit 110 forms at least a part of a computing device 210.

[0010] At least a portion of the first nonlinear element 50A is provided in the first region 81a of the first face F1, at least a portion of the second nonlinear element 50B is provided in the second region 81b of the first face F1, and at least a portion of the third nonlinear element 50C is provided on the second face F2.

[0011] The second surface F2 is spaced from the first surface F1 in a first direction. The second surface F2 is aligned with the first surface F1. The second surface F2 is substantially parallel to the first surface F1. The first direction intersects with the first surface F1.

[0012] In this example, the electronic circuit 110 includes a first substrate 81. A first surface F1 is one surface (e.g., the top surface) of the first substrate 81. A second surface F2 is another surface (e.g., the bottom surface) of the first substrate 81. FIG. 1(b) is a transparent plan view of the first substrate 81.

[0013] The direction from the second surface F2 to the first surface F1 is defined as the Z-axis direction. One direction perpendicular to the Z-axis direction is defined as the X-axis direction. The direction perpendicular to the Z-axis direction and the X-axis direction is defined as the Y-axis direction. The first surface F1 and the second surface F2 are substantially parallel to the XY plane. The above first direction corresponds to, for example, the Z-axis direction.

[0014] The first nonlinear element 50A includes a first-element Josephson junction 51. The first-element Josephson junction 51 is provided on the first face F1. The second nonlinear element 50B includes a second-element Josephson junction 52. The second-element Josephson junction 52 is provided on the first face F1. At least a portion of the first nonlinear element 50A includes, for example, the first-element Josephson junction 51. At least a portion of the second nonlinear element 50B includes the second-element Josephson junction 52.

[0015] The first nonlinear element 50A is one of a plurality of quantum bits provided in the computing device 210. The second nonlinear element 50B is another of a plurality of quantum bits provided in the computing device 210. These nonlinear elements are, for example, nonlinear resonators. The plurality of quantum bits are, for example, transmon quantum bits.

[0016] The third nonlinear element 50C includes a Josephson junction circuit 53. At least a portion of the Josephson junction circuit 53 is provided on the second face F2. The at least a portion of the third nonlinear element 50C includes, for example, the Josephson junction circuit 53.

[0017] The third nonlinear element 50C can be coupled to the first nonlinear element 50A. The third nonlinear element 50C can be coupled to the second nonlinear element 50B. The third nonlinear element 50C is, for example, a coupler. In the example of the electronic circuit 110, the third nonlinear element 50C can be coupled (e.g., capacitively coupled) to the first nonlinear element 50A. The third nonlinear element 50C can be coupled (e.g., capacitively coupled) to the second nonlinear element 50B.

[0018] In the embodiment, at least a portion of the third nonlinear element 50C functioning as a coupler is provided on a different surface from the first nonlinear element 50A and the second nonlinear element 50B functioning as quantum bits. For example, wiring need not be provided between adjacent quantum bits on the first surface F1. For example, wiring connection to the quantum bits becomes easy. For example, wiring need not be provided between the coupler on the second surface F2. For example, wiring connection to the coupler becomes easy. For example, crosstalk between wiring can be reduced. According to the embodiment, an electronic circuit capable of improving scalability can be provided. According to the embodiment, an electronic circuit and a computing device capable of improving characteristics can be provided.

[0019] For example, a reference example may be considered in which the qubit and the coupler are provided in the same plane. In this reference example, for example, the qubit may have difficulty accessing the coupler. In this reference example, the qubit may have difficulty accessing the coupler.

[0020] In contrast, in the embodiment, the qubit and the coupler are provided on different planes. This allows, for example, easier access to the coupler and the qubit. The easier access stabilizes the gate operation of the qubit. For example, the stability of the qubit is improved. For example, a good off state is more easily obtained.

[0021] As shown in FIG. 1(b), in this example, the Josephson junction circuit 53 includes a first Josephson junction 21, a second Josephson junction 22, and a third Josephson junction 23. The first Josephson junction 21, the second Josephson junction 22, and the third Josephson junction 23 are provided on a second plane F2. The third nonlinear element 50C further includes a first conductive member 25a, a second conductive member 25b, and a third conductive member 25c. The first conductive member 25a connects the first Josephson junction 21 to the third Josephson junction 23. The second conductive member 25b connects the second Josephson junction 22 to the third Josephson junction 23. The third conductive member 25c connects the first Josephson junction 21 to the second Josephson junction 22. These connections may be, for example, electrical connections. The first conductive member 25a, the second conductive member 25b, and the third conductive member 25c are, for example, superconductors.

[0022] The first Josephson junction 21, the second Josephson junction 22, the third Josephson junction 23, the first conductive member 25a, the second conductive member 25b, and the third conductive member 25c form a loop 50r. The first nonlinear element 50A can be coupled to the first conductive member 25a. The second nonlinear element 50B can be coupled to the second conductive member 25b. For example, the first nonlinear element 50A can be capacitively coupled to the first conductive member 25a. For example, the second nonlinear element 50B can be capacitively coupled to the second conductive member 25b.

[0023] FIG. 3 is a schematic diagram illustrating an electronic circuit and a computing device according to the first embodiment. 3, the first conductive member 25a connects one end 21e of the first Josephson junction 21 to one end 23e of the third Josephson junction 23. The second conductive member 25b connects one end 22e of the second Josephson junction 22 to the other end 23f of the third Josephson junction 23. The third conductive member 25c connects the other end 21f of the first Josephson junction 21 to the other end 22f of the second Josephson junction 22.

[0024] 3, in the electronic circuit 110, a first element capacitor 41 may be connected in parallel to a first element Josephson junction 51. A second element capacitor 42 may be connected in parallel to a second element Josephson junction 52.

[0025] A first capacitor 11 may be connected in parallel to the first Josephson junction 21. A second capacitor 12 may be connected in parallel to the second Josephson junction 22. For example, the first element Josephson junction 51 may be capacitively coupled to the first Josephson junction 21 and the third Josephson junction 23 via a third capacitor 13. For example, the second element Josephson junction 52 may be capacitively coupled to the second Josephson junction 22 and the third Josephson junction 23 via a fourth capacitor 14. A fifth capacitor 15 may be connected in parallel to the third Josephson junction 23.

[0026] As will be described later, the first Josephson junction 21 may be a first inductor, and the second Josephson junction 22 may be a second inductor.

[0027] 1(a), a third capacitor 13 and a fourth capacitor 14 are provided on the first surface F1. These capacitors are electrically connected to conductive members provided on the second surface F2 through vias provided in the first substrate 81.

[0028] As shown in FIGS. 1(a), 1(b), and 2, the electronic circuit 110 further includes a first element conductive portion 51v and a second element conductive portion 52v. The first element conductive portion 51v extends in a first direction (Z-axis direction) through the first substrate 81. The first element conductive portion 51v is electrically connected to the first nonlinear element 50A. Alternatively, the first element conductive portion 51v can be coupled (e.g., capacitively coupled) to the first nonlinear element 50A. In this example, the first element conductive portion 51v is capacitively coupled to the first nonlinear element 50A via the third capacitor 13. The first element conductive portion 51v is electrically connected to the first conductive member 25a. Alternatively, the first element conductive portion 51v can be coupled (e.g., capacitively coupled) to the first conductive member 25a. In this example, the first element conductive portion 51v is electrically connected to the first conductive member 25a.

[0029] The second element conductive portion 52v extends in the first direction (Z-axis direction) through the first substrate 81. The second element conductive portion 52v is electrically connected to the second nonlinear element 50B. Alternatively, the second element conductive portion 52v can be coupled (e.g., capacitively coupled) to the second nonlinear element 50B. In this example, the second element conductive portion 52v is capacitively coupled to the second nonlinear element 50B via the fourth capacitor 14. The second element conductive portion 52v is electrically connected to the second conductive member 25b. Alternatively, the second element conductive portion 52v can be coupled (e.g., capacitively coupled) to the second conductive member 25b. In this example, the second element conductive portion 52v is electrically connected to the second conductive member 25b.

[0030] The first element conductive portion 51v and the second element conductive portion 52v are, for example, TSVs (Through-Substrate Vias). Connections using TSVs provide high-density and stable connections.

[0031] 4A and 4B are schematic cross-sectional views illustrating a part of the electronic circuit according to the first embodiment. FIG. 4(a) is a cross-sectional view of the first capacitor 11. FIG. 4(b) is a cross-sectional view of the second capacitor 12. As shown in FIG. 4(a), the first capacitor 11 includes a conductive member 11u and a conductive member 11v. These conductive members extend along the first direction (Z-axis direction) on at least a portion of the first substrate 81. As shown in FIG. 4(b), the second capacitor 12 includes a conductive member 12u and a conductive member 12v. These conductive members extend along the first direction (Z-axis direction) on at least a portion of the first substrate 81. Use of these conductive members allows for a capacitor with a small area to be obtained. These conductive members may be TSVs.

[0032] 1(a), in this example, the first element capacitor 41 and the second element capacitor 42 are provided on the first surface F1. These element capacitors may also be formed by conductive members extending through the first substrate 81 in the Z-axis direction.

[0033] 5(a) to 5(e) are schematic cross-sectional views illustrating a part of the electronic circuit according to the first embodiment. 5(a), the first element Josephson junction 51 includes, for example, a conductive film 55a, a conductive film 55b, and an insulating film 55i. The insulating film 55i is provided between a part of the conductive film 55a and a part of the conductive film 55b.

[0034] 5(b), the second element Josephson junction 52 includes, for example, a conductive film 55c, a conductive film 55d, and an insulating film 55j. The insulating film 55j is provided between a part of the conductive film 55c and a part of the conductive film 55d.

[0035] 5(c), the first Josephson junction 21 includes, for example, a conductive film 26a, a conductive film 26b, and an insulating film 26i. The insulating film 26i is provided between a part of the conductive film 26a and a part of the conductive film 26b.

[0036] 5(d), the second Josephson junction 22 includes, for example, a conductive film 26c, a conductive film 26d, and an insulating film 26j. The insulating film 26j is provided between a part of the conductive film 26c and a part of the conductive film 26d.

[0037] 5(e), the third Josephson junction 23 includes, for example, a conductive film 26e, a conductive film 26f, and an insulating film 26k. The insulating film 26k is provided between a part of the conductive film 26e and a part of the conductive film 26f.

[0038] These conductive films include, for example, at least one selected from the group consisting of Al, Nb, NbN, TiN, NbTiN, and Ta. These materials are superconducting materials. The insulating film includes, for example, at least one selected from the group consisting of Al2O3, Nb2O5, NbO2, NbO, and AlN. The first substrate 81 includes, for example, at least one selected from the group consisting of Si and sapphire. The first substrate 81 is, for example, insulating.

[0039] As shown in FIG. 1(a), in this example, the electronic circuit 110 includes a first element resonator 51O, a first element terminal 51T, a second element resonator 52O, and a second element terminal 52T. The first element resonator 51O can be coupled (e.g., capacitively coupled) to the first nonlinear element 50A. The first element terminal 51T can be coupled (e.g., capacitively coupled) to the first element resonator 51O. The second element resonator 52O can be coupled (e.g., capacitively coupled) to the second nonlinear element 50A. B The second element terminal 52T can be coupled (for example, capacitively coupled) to the second element resonator 52O.

[0040] The state of the first nonlinear element 50A can be detected by the first element resonator 51O and the first element terminal 51T. A signal corresponding to the state of the first nonlinear element 50A can be obtained via the first element resonator 51O and the first element terminal 51T. The state of the second nonlinear element 50B can be detected by the second element resonator 52O and the second element terminal 52T. 2A signal corresponding to the state of the second nonlinear element 50B can be obtained via T. The element resonator and the element terminal correspond to, for example, a readout unit.

[0041] At least one of at least a part of the first element resonator 51O, at least a part of the first element terminal 51T, at least a part of the second element resonator 52O, and at least a part of the second element terminal 52T may be provided on the first surface F1.

[0042] 3, the electronic circuit 110 (computing device 210) may include a magnetic flux control unit 60. The magnetic flux control unit 60 can control the magnetic flux Φ in the space SP within the loop 50r. For example, the magnetic flux control unit 60 can modulate the magnetic flux Φ in the space SP.

[0043] 3, the computing device 210 may include an electronic circuit 110 and a control unit 70. The control unit 70 can control the magnetic flux control unit 60. This allows the control unit 70 to control the magnetic flux Φ in the space SP.

[0044] In this example, the magnetic flux control unit 60 includes a first control conductive member 61. The control unit 70 is connected to the first control conductive member 61. A magnetic flux control signal is supplied from the control unit 70 to the first control conductive member 61. A magnetic field corresponding to the magnetic flux control signal is generated from the first control conductive member 61. This magnetic field controls the magnetic flux Φ in the space SP within the loop 50r. The first control conductive member 61 is one example of the magnetic flux control unit 60. The control unit 70 can change the magnetic flux Φ by modulating the current supplied to the first control conductive member 61.

[0045] For example, the third nonlinear element 50C (coupler) has multiple modes (for example, two modes). In the embodiment, the resonant frequencies of the multiple modes can be lowered. For example, it is easy to make the resonant frequencies of the multiple modes closer to the resonant frequencies of the first nonlinear element 50A and the second nonlinear element 50B. This allows for a strong coupling strength to be obtained. According to the embodiment, controllability can be improved.

[0046] By controlling the magnetic flux Φ, the coupling strength can be changed. For example, the coupling strength can be set to substantially zero, thereby eliminating (turning off) the coupling. As will be described later, by controlling the third nonlinear element 50C (coupler), two-qubit gate operations can be performed at high speed. A coupler and a computing device that can improve controllability can be provided.

[0047] As shown in Fig. 1(a), a conductive layer at a fixed potential (e.g., ground potential GND) may be provided around the first nonlinear element 50A and the second nonlinear element 50B. As shown in Fig. 1(b), a conductive layer at a fixed potential (e.g., ground potential GND) may be provided around the third nonlinear element 50C.

[0048] 2, a conductive layer provided on the first surface F1 and set to a fixed potential (e.g., ground potential GND) and a conductive layer provided on the second surface F2 and set to a fixed potential (e.g., ground potential GND) may be electrically connected by connection portions 81C and 81D. These connection portions extend through the first substrate 81 along the Z-axis direction.

[0049] As shown in FIGS. 1(a) and 1(b), the first nonlinear element 50A may be connected to another nonlinear element 50D via a conductive member 55u. As shown in FIGS. 1(a) and 1(b), the second nonlinear element 50B may be connected to another nonlinear element 50E via a conductive member 55v. The other nonlinear element 50D and the other nonlinear element 50E may be, for example, couplers. The other nonlinear element 50D may be connected to yet another nonlinear element (another quantum bit, not shown). The other nonlinear element 50E may be connected to yet another nonlinear element (another quantum bit, not shown). The conductive member 55u and the conductive member 55v may extend in the Z-axis direction through at least a portion of the first substrate 81, for example. These conductive members may be TSVs.

[0050] The first nonlinear element 50A may be connected to another nonlinear element 50F and another nonlinear element 50H. The second nonlinear element 50B may be connected to another nonlinear element 50G and another nonlinear element 50I. The nonlinear elements 50F, 50G, 50H, and 50I may be, for example, couplers. The nonlinear elements 50F, 50G, 50H, and 50I may be connected to yet another nonlinear element (another qubit, not shown).

[0051] The first nonlinear element 50A and the second nonlinear element 50B function as two quantum bits. The first nonlinear element 50A and the second nonlinear element 50B have a plurality of energy levels, of which the two lowest ones can be used as two states of the quantum bit. The two lowest energy levels correspond to the ground state and the first excited state. The two states of the quantum bit correspond to computational basis states. For example, the resonant frequency of the first nonlinear element 50A corresponds to the value obtained by converting the energy difference between the two lowest states of the first nonlinear element 50A into a frequency. For example, the resonant frequency of the second nonlinear element 50B corresponds to the value obtained by converting the energy difference between the two lowest states of the second nonlinear element 50B into a frequency. Energy can be converted into a frequency by dividing it by Planck's constant h.

[0052] As shown in FIG. 1, the third nonlinear element 50C (coupler) may include a first control conductive member 61. The first control conductive member 61 can apply a magnetic field to the space SP (loop 50r). For example, a magnetic field is generated by a current supplied to the first control conductive member 61. The generated magnetic field is applied to the space SP (loop 50r). As will be described later, the coupling strength between the first nonlinear element 50A and the second nonlinear element 50B changes depending on the magnetic flux Φ (magnetic flux based on the magnetic field) in the space SP (loop 50r).

[0053] FIG. 6 is a schematic cross-sectional view illustrating the electronic circuit according to the first embodiment. 7A and 7B are schematic plan views illustrating a part of the electronic circuit according to the first embodiment. 6, the electronic circuit 111 according to the embodiment includes a second substrate 82, a first opposing electrode 51C, and a second opposing electrode 52C. The configuration of the electronic circuit 111 other than these may be similar to the configuration of the electronic circuit 110. The computing device 211 includes the electronic circuit 111.

[0054] The second substrate 82 includes a third surface F3 and a fourth surface F4. The fourth surface F4 faces the first surface F1. The fourth surface F4 is located between the first surface F1 and the third surface F3. The fourth surface F4 is, for example, a lower surface. The third surface F3 is, for example, an upper surface.

[0055] The first opposing electrode 51C is provided on the fourth face F4. The second opposing electrode 52C is provided on the fourth face F4. The first opposing electrode 51C can be coupled (e.g., capacitively coupled) to the first element terminal 51T. The second opposing electrode 52C can be coupled (e.g., capacitively coupled) to the second element terminal 52T.

[0056] 6, 7(a) and 7(b), a first readout electrode 51R, a first readout conductive portion 51Rv, a second readout electrode 52R and a second readout conductive portion 52Rv may be provided. Electrode 52R is provided on the third surface F3. The first readout conductive portion 51Rv extends in the first direction (for example, the Z-axis direction) in the second substrate 82. 1 Rv electrically connects the first opposing electrode 51C to the first readout electrode 51R. The second readout conductive portion 52Rv extends in a first direction (e.g., the Z-axis direction) in the second substrate 82. The second readout conductive portion 52Rv electrically connects the second opposing electrode 52C to the second readout electrode 52R.

[0057] 7(a), the first readout electrode 51R and the second readout electrode 52R may be connected to the control unit 70. The control unit 70 can obtain a signal corresponding to the state of the first nonlinear element 50A and a signal corresponding to the state of the second nonlinear element 50B via these electrodes.

[0058] As shown in FIG. 7(b), a first control terminal 51NT and a second control terminal 52NT may be provided on the fourth surface F4. As shown in FIG. 7(a), a first control electrode 51N and a second control electrode 52N may be provided on the third surface F3. The first control terminal 51NT is connected to the first control electrode 51N via a conductive portion 51Nv. The second control terminal 52NT is connected to the second control electrode 52N via a conductive portion 52Nv. A control unit 70 is connected to the first control electrode 51N and the second control electrode 52N. The characteristics of the first nonlinear element 50A may be controlled by a signal supplied from the control unit 70 to the first control electrode 51N. The characteristics of the second nonlinear element 50B may be controlled by a signal supplied from the control unit 70 to the second control electrode 52N. The conductive portions 51Nv and 52Nv extend in the first direction (Z-axis direction) through at least a portion of the second substrate 82. These conductive parts may be TSVs.

[0059] Thus, the electronic circuit 111 may include a first control terminal 51NT and a second control terminal 52NT. A first control signal Sc1 for controlling the first nonlinear element 50A can be applied to the first control terminal 51NT. A second control signal Sc2 for controlling the second nonlinear element 50B can be applied to the second control terminal 52NT. The first control signal Sc1 is an excitation signal for the first nonlinear element 50A. The second control signal Sc2 is an excitation signal for the second nonlinear element 50B.

[0060] 7(a) and 7(b), a conductive layer provided on the third surface F3 and set to a fixed potential (e.g., ground potential GND) and a conductive layer provided on the fourth surface F4 and set to a fixed potential (e.g., ground potential GND) may be electrically connected by a connection portion 82C and a connection portion 82D. These connection portions extend along the Z-axis direction within the second substrate 82.

[0061] 8A and 8B are schematic plan views illustrating a part of the electronic circuit according to the first embodiment. As shown in Figures 6, 8(a) and 8(b), the electronic circuit 111 may include a third substrate 83. 3The electronic circuit 111 includes a fifth surface F5 and a sixth surface F6. The fifth surface F5 faces the second surface F2. The fifth surface F5 is between the sixth surface F6 and the second surface F2. The fifth surface F5 is, for example, the upper surface. The sixth surface F6 is, for example, the lower surface. The electronic circuit 111 includes a magnetic flux control unit 60. The magnetic flux control unit 60 is provided on the fifth surface F5. The magnetic flux control unit 60 is capable of controlling the magnetic flux Φ in the space SP within the loop 50r (see FIG. 3). For example, a control unit 70 is provided. The control unit 70 controls the magnetic flux control unit 60 to control the magnetic flux Φ.

[0062] In this example, the magnetic flux control section 60 includes a first control conductive member 61. Thus, the electronic circuit 111 may include the first control conductive member 61. In this example, the electronic circuit 111 includes a first control conductive portion 61u and a second control conductive portion 61v.

[0063] As shown in FIGS. 6 and 8(a), the first control conductive member 61 is provided on the fifth face F5. The first control conductive portion 61u extends in a first direction (e.g., the Z-axis direction) through the third substrate 83. The first control conductive portion 61u is electrically connected to a portion of the first control conductive member 61. The second control conductive portion 61v extends in the first direction (e.g., the Z-axis direction) through the third substrate 83. The second control conductive portion 61v is electrically connected to another portion of the first control conductive member 61.

[0064] As shown in Fig. 8(b), the control unit 70 is connected to the first control conductive member 61 via the first control conductive member 61u and the second control conductive member 61v. A magnetic field is generated by a signal (current) supplied from the control unit 70 to the first control conductive member 61. The generated magnetic field is applied to the space SP within the loop 50r (see Fig. 3). The magnetic flux Φ in the space SP is controlled.

[0065] 6, the conductive layer of the ground potential GND provided on the first face F1 and the conductive layer of the ground potential GND provided on the fourth face F4 may be electrically connected by a connection portion 58a, and the conductive layer of the ground potential GND provided on the second face F2 and the conductive layer of the ground potential GND provided on the fifth face F5 may be electrically connected by a connection portion 58b.

[0066] 8(a) and 8(b), a conductive layer provided on the fifth face F5 and set to a fixed potential (e.g., ground potential GND) and a conductive layer provided on the sixth face F6 and set to a fixed potential (e.g., ground potential GND) may be electrically connected by connection portions 83C and 83D. These connection portions extend along the Z-axis direction within the third substrate 83.

[0067] Some examples of electronic circuits and computing devices are described below. 9A and 9B are schematic plan views illustrating the electronic circuit according to the first embodiment. As shown in FIG. 9(a), in the electronic circuit 112, a first element Josephson junction 51 and a second element Josephson junction 52 are provided on a first surface F1. As shown in FIG. 9(b), first to third Josephson junctions 21 to 23 are provided on a second surface F2. Furthermore, a first control conductive member 61 is provided on the second surface F2. A magnetic flux control signal (e.g., a control current 61i) is supplied to the first control conductive member 61 from a control unit 70. A magnetic field generated by the control current 61i is applied to a space SP within the loop 50r. The magnetic flux Φ can be controlled by controlling the control current 61i. The computing device 212 includes the electronic circuit 112 and the control unit 70.

[0068] 10A and 10B are schematic plan views illustrating the electronic circuit according to the first embodiment. 10(a) and 10(b), in the electronic circuit 113, the first element capacitor 41, the second element capacitor 42, the third capacitor 13, and the fourth capacitor 14 are formed by conductive portions extending in the first direction (Z-axis direction) on the first substrate 81. The computing device 213 includes the electronic circuit 113 and a control unit 70.

[0069] 11A and 11B are schematic plan views illustrating the electronic circuit according to the first embodiment. 11(a) and 11(b), in the electronic circuit 114, the first element capacitor 41, the second element capacitor 42, the first capacitor 11, the second capacitor 12, the third capacitor 13, and the fourth capacitor 14 are formed by conductive parts extending in the first direction (Z-axis direction) on the first substrate 81. The computing device 214 includes the electronic circuit 114 and a control unit 70.

[0070] 12A and 12B are schematic plan views illustrating the electronic circuit according to the first embodiment. 12(a) and 12(b), in the electronic circuit 115, the first control conductive member 61 includes a coaxial cable. The first element capacitor 41, the second element capacitor 42, the first capacitor 11, the second capacitor 12, the third capacitor 13, and the fourth capacitor 14 are formed by conductive parts extending in the first direction (Z-axis direction) on the first substrate 81. The computing device 215 includes the electronic circuit 115 and a control unit 70.

[0071] 13A and 13B are schematic plan views illustrating the electronic circuit according to the first embodiment. 13(a) and 13(b), in the electronic circuit 116, the first control conductive member 61 includes a coaxial cable. The first element Josephson junction 51 is provided between an annular conductive portion and a conductive portion provided within the annular conductive portion. The second element Josephson junction 52 is provided between an annular conductive portion and a conductive portion provided within the annular conductive portion. The computing device 216 includes the electronic circuit 116 and a control unit 70.

[0072] 14A and 14B are schematic plan views illustrating the electronic circuit according to the first embodiment. As shown in FIGS. 14(a) and 14(b), in the electronic circuit 117, the first control conductive member 61 includes a coaxial cable. The first element Josephson junction 51 is provided between an annular conductive portion and a conductive portion provided within the annular conductive portion. The second element Josephson junction 52 is provided between an annular conductive portion and a conductive portion provided within the annular conductive portion. The third capacitor 13 and the fourth capacitor 14 include portions extending along the first face F1. The computing device 217 includes the electronic circuit 117 and a control unit 70.

[0073] 15A and 15B are schematic plan views illustrating the electronic circuit according to the first embodiment. FIG. 16 is a schematic cross-sectional view illustrating the electronic circuit according to the first embodiment. 16, the electronic circuit 120 includes a first substrate 81 and a second substrate 82. The first surface F1 is one surface (e.g., the upper surface) of the first substrate 81. The second surface F2 is one surface (e.g., the lower surface) of the second substrate 82. The second surface F2 faces the first surface F1.

[0074] The first nonlinear element 50A is provided in the first region 81a of the first face F1, the second nonlinear element 50B is provided in the second region 81b of the first face F1, and the third nonlinear element 50C is provided on the second face F2.

[0075] 15(a), the first element Josephson junction 51 included in the first nonlinear element 50A is provided in a first region 81a of the first face F1, and the second element Josephson junction 52 included in the second nonlinear element 50B is provided in a second region 81b of the first face F1.

[0076] As shown in FIG. 15(b), at least a portion of the Josephson junction circuit 53 of the third nonlinear element 50C is provided on the second face F2. The second face F2 is spaced apart from the first face F1. The third nonlinear element 50C can be coupled to the first nonlinear element 50A. The third nonlinear element 50C can be coupled to the second nonlinear element 50B. For example, the third nonlinear element 50C can be inductively coupled to the first nonlinear element 50A. For example, the third nonlinear element 50C can be inductively coupled to the second nonlinear element 50B.

[0077] In the electronic circuit 120, the Josephson junction circuit 53 also includes a first Josephson junction 21, a second Josephson junction 22, and a third Josephson junction 23. These Josephson junctions are provided on the second surface F2. The third nonlinear element 50C includes a first conductive member 25a, a second conductive member 25b, and a third conductive member 25c. These conductive members are provided on the second surface F2. The first conductive member connects the first Josephson junction 21 to the third Josephson junction 23. The second conductive member 25b connects the second Josephson junction 22 to the third Josephson junction 23. The third conductive member 25c connects the first Josephson junction 21 to the second Josephson junction 22. The first Josephson junction, the second Josephson junction, the third Josephson junction, the first conductive member, the second conductive member, and the third conductive member form a loop 50r. The first nonlinear element 50A is connectable to the first conductive member 25a. The second nonlinear element 50B can be coupled to the second conductive member 25b. In the electronic circuit 120, the first nonlinear element 50A can be inductively coupled to the first conductive member 25a. The second nonlinear element 50B can be inductively coupled to the second conductive member 25b.

[0078] The electronic circuit 120 includes the circuit described with reference to Fig. 3. The electronic circuit 120 may include first to fifth capacitors 11 to 15. The first nonlinear element 50A may include a first element capacitor 41. The second nonlinear element 50B may include a second element capacitor 42.

[0079] As shown in FIG. 15(b), a magnetic flux control unit 60 may be provided. The magnetic flux control unit 60 includes a first control conductive member 61. A magnetic flux control signal (control current 61i) is supplied to the first control conductive member 61 from the control unit 70. A magnetic field corresponding to the magnetic flux control signal is generated from the first control conductive member 61. This magnetic field controls the magnetic flux Φ in the space SP within the loop 50r. The control unit 70 can change the magnetic flux Φ by modulating the current supplied to the first control conductive member 61. The computing device 218 includes an electronic circuit 120 and the control unit 70.

[0080] Below, examples of characteristics of a computing device (for example, computing device 210) according to an embodiment will be described. In the following description, the critical current of the first element Josephson junction 51 is 56.6 nA. The critical current of the second element Josephson junction 52 is 45.9 nA. The capacitance of the first element capacitor 41 is 43.6 fF. The capacitance of the second element capacitor 42 is 43.6 fF. The critical current of the first Josephson junction 21 is 64.4 nA. The critical current of the second Josephson junction 22 is 50.0 nA. The critical current of the third Josephson junction 23 is 14.8 nA. The capacitance of the first capacitor 11 is 19.4 fF. The capacitance of the second capacitor 12 is 19.4 fF. The capacitance of the third capacitor 13 is 6.46 fF. The capacitance of the fourth capacitor 14 is 6.46 fF. The capacitance of the fifth capacitor 15 is 0.969 fF.

[0081] FIG. 17 is a graph illustrating the characteristics of the computing device according to the first embodiment. The horizontal axis of FIG. 17 represents the magnetic flux MF1 in the space SP (loop 50r). The magnetic flux MF1 (=2Φ / Φ0) is normalized by the magnetic flux quantum Φ0 and made dimensionless. The vertical axis of FIG. 17 corresponds to the frequency fo1. FIG. 17 illustrates the resonant frequency fb1 of the first nonlinear element 50A and the resonant frequency fb2 of the second nonlinear element 50B. The first nonlinear element 50A corresponds to, for example, the first quantum bit. The second nonlinear element 50B corresponds to, for example, the second quantum bit. The nonlinear element is, for example, a nonlinear resonator (transmon quantum bit). The resonant frequency of the nonlinear element corresponds to the value obtained by dividing the energy difference between the two lowest states of the nonlinear element by Planck's constant h and converting it into a frequency.

[0082] 17 illustrates frequencies fc1 and fc2. The frequency fc1 corresponds to one frequency of a plurality of modes (e.g., two modes) in the third nonlinear element 50C (coupler). The frequency fc2 corresponds to another frequency of a plurality of modes (e.g., two modes) in the third nonlinear element 50C (coupler).

[0083] 17, in the computing device 210 according to the embodiment, when the magnetic flux MF1 changes, the frequencies fc1 and fc2 change. In particular, the frequency fc2 changes significantly. In this example, when the magnetic flux MF1 is approximately 0.61, the frequencies fc1 and fc2 approach each other. The first magnetic flux value Mv1 is approximately 0.61.

[0084] 17, the resonant frequency fb1 of the first nonlinear element 50A and the resonant frequency fb2 of the second nonlinear element 50B are substantially constant when the magnetic flux MF1 changes. In this example, the resonant frequency fb1 of the first nonlinear element 50A is approximately 10.0 GHz. The resonant frequency fb2 of the second nonlinear element 50B is approximately 8.4 GHz.

[0085] Thus, in the embodiment, the frequencies fc1 and fc2 are relatively close to the resonant frequencies fb1 and fb2. The third nonlinear element 50C (coupler) has a plurality of modes (at least two modes). That is, the coupler can resonate in a plurality of modes. The resonant frequencies (frequencies fc1 and fc2) in each of the plurality of modes are higher than the resonant frequencies fb1 and fb2, respectively, and lower than the sum of the resonant frequencies fb1 and fb2, in the vicinity of the first magnetic flux value Mv1 (magnetic flux values ​​at which the frequencies fc1 and fc2 are close to each other). In the embodiment, there exists a state in which the resonant frequencies (frequencies fc1 and fc2) in each of the plurality of modes are lower than the sum of the resonant frequencies fb1 and fb2.

[0086] For example, when the coupling between the first nonlinear element 50A and the second nonlinear element 50B is substantially eliminated, the resonant frequency in each of the multiple modes in the third nonlinear element 50C is higher than the resonant frequency fb1 of the first nonlinear element 50A, higher than the resonant frequency fb2 of the second nonlinear element 50B, and lower than the sum of the resonant frequency fb1 of the first nonlinear element 50A and the resonant frequency fb2 of the second nonlinear element 50B.

[0087] FIG. 18 is a graph illustrating the characteristics of the computing device according to the first embodiment. The horizontal axis in Figure 18 is the magnetic flux MF1. The vertical axis is the coupling strength CSZZ of the residual coupling (so-called ZZ coupling). The ZZ coupling corresponds to a state in which fb1 + fb2 - fb3 does not become zero due to the residual coupling for the frequency fb3 corresponding to when both quantum bits are in the "1 state." This "deviation" in the ZZ coupling corresponds to the coupling strength CSZZ.

[0088] In this example, when the magnetic flux Mf1 is about 0.61 (first magnetic flux value Mv1), the coupling strength Cszz becomes substantially zero. As shown in Figure 18, when the magnetic flux Mf1 is about 0.61, the coupling strength Cszz for the residual coupling can be made substantially zero. For example, a robust zero Zz coupling is obtained.

[0089] For example, the magnetic flux MF1 is increased or decreased between a first state ST1 in which the magnetic flux MF1 has a first magnetic flux value Mv1 and a second state ST2 in which the magnetic flux MF1 is greater than the first magnetic flux value Mv1. This allows a two-qubit gate to be implemented. Such an operation corresponds to, for example, the first operation. For example, in the second state ST2, the magnetic flux MF1 is 1.

[0090] In the first operation, for example, the magnetic flux Φ (corresponding to the magnetic flux MF1) is increased in a pulsed manner from the first magnetic flux value Mv1 (first state ST1) to form the second state ST2. Then, the magnetic flux Φ (corresponding to the magnetic flux MF1) is decreased back to the first magnetic flux value Mv1. This implements a two-qubit gate. In the two-qubit gate, the phase of the |01> state relative to the |00> state is changed by θ 01 In the two-qubit gate, the phase of the |10> state relative to the |00> state is rotated by θ 10 In the two-qubit gate, the phase of the |11> state relative to the |00> state is rotated by θ 11 Rotate by θ 11 is θ 01 and θ 10 and the sum (i.e., θ 01 +θ 10 This phase shift (θ 11 -θ 01 -θ 10 ) corresponds to the gate rotation angle.

[0091] FIG. 19 is a graph illustrating the characteristics of the computing device according to the first embodiment. FIG. 19 illustrates the characteristics of the first operation described above. The horizontal axis of FIG. 19 is the gate rotation angle θ1 divided by π, where π is the constant of the circumference of a circle. The vertical axis is the fidelity FT1. The gate time is approximately 12 ns. As shown in FIG. 19, a high fidelity FT1 of 99.98% or more can be obtained with a high-speed gate.

[0092] FIG. 20 is a graph illustrating the characteristics of the computing device according to the first embodiment. The horizontal axis of FIG. 20 represents the magnetic flux MF1. The vertical axis represents the coupling strength CS1 between the first nonlinear element 50A and the second nonlinear element 50B. The coupling strength CS1 is the coupling strength between the |01> state and the |10> state. As shown in FIG. 20, when the magnetic flux MF1 has the first magnetic flux value MV1, the coupling strength CS1 becomes zero. At this time, the coupling is turned off. As shown in FIG. 20, when the magnetic flux MF1 changes, the coupling strength CS1 changes. The coupling strength CS1 can be controlled by controlling the magnetic flux MF1. For example, the range of change in the coupling strength CS1 is about 20 MHz. That is, the coupling strength CS1 can be adjusted in the range of -20 MHz to 20 MHz. Such an operation corresponds to, for example, the second operation.

[0093] For example, in the second operation, the magnetic flux Φ (magnetic flux MF1) is modulated at a frequency of "fb1-fb2." The modulation envelope may be, for example, pulse-shaped. In this second operation, the two-qubit gate is a rotation gate in which the probability of the |01> state and the probability of the |10> state are interchanged. In this rotation gate (a rotation gate in which probabilities are interchanged), the rotation angle corresponds to the rotation angle of the rotation matrix for the probability amplitude vector.

[0094] In this way, the control unit 70 can control the magnetic flux Φ (magnetic flux MF1) in the space SP to change the coupling strength CS1 between the first nonlinear element 50A and the second nonlinear element 50B.

[0095] FIG. 21 is a graph illustrating the characteristics of the computing device according to the first embodiment. FIG. 21 illustrates the characteristics of the second operation described above. The horizontal axis of FIG. 20 is the gate rotation angle θ2 divided by π. This gate rotation angle θ2 corresponds to the rotation angle of the rotation matrix for the probability amplitude vector in a rotation gate where probabilities are swapped. The vertical axis is the fidelity FT1. The gate time is approximately 12 ns. As shown in FIG. 21, a high fidelity FT1 of 99.98% or more can be obtained with a high-speed gate. In FIG. 21, the gate with a gate rotation angle θ2 of 0.25π corresponds to the "square root of iSWAP gate."

[0096] The control unit 70 can perform, for example, at least one of a first operation and a second operation. In the first operation, the control unit 70 performs two-qubit operations on the first nonlinear element 50A and the second nonlinear element 50B by varying the magnetic flux Φ between a first value and a second value greater than the first value. The first value is a value (0.5Φ0 × Mv1) corresponding to the above-mentioned first magnetic flux value Mv1. The second value may be, for example, substantially 0.5Φ0. In the second operation, the control unit 70 performs two-qubit operations on the first nonlinear element 50A and the second nonlinear element 50B by modulating the magnetic flux Φ with an AC current.

[0097] The characteristics of the electronic circuit and the computing device according to the embodiment will be described below. The Lagrangian of the system including the first nonlinear element 50A, the second nonlinear element 50B, and the third nonlinear element 50C (coupler) is expressed by the following first equation.

number

[0098] The first term on the right side of the first equation is the Lagrangian of the first nonlinear element 50A. The second term on the right side of the first equation is the Lagrangian of the second nonlinear element 50B. The third term on the right side of the first equation is the Lagrangian of the coupler. The fourth term on the right side of the first equation is the Lagrangian that represents the interaction between the coupler, the first nonlinear element 50A, and the second nonlinear element 50B.

[0099] The Lagrangian of the first nonlinear element 50A is expressed by the following second equation: In the second equation, “C1” is the capacitor of the first element capacitor 41.

number

[0100] In the second equation, the reduced flux quantum φ0 corresponds to 1 / (2π) times the flux quantum Φ0.

[0101] The Lagrangian of the second nonlinear element 50B is expressed by the following third equation: In the third equation, "C2" is the capacitor of the second element capacitor .

number

[0102] The Lagrangian representing the interaction between the coupler, the first nonlinear element 50A, and the second nonlinear element 50B is expressed by the following fourth equation. c " are the capacitors of the third capacitor 13 and the fourth capacitor 14, respectively.

number

[0103] The Lagrangian of the coupler is expressed by the following equation 5: In equation 5, "C" is the capacitance of each of the first capacitor 11 and the second capacitor 12.

number

[0104] Here, φ is a magnetic flux operator. φ has a relationship with the phase difference θ expressed by the following equation (6).

[0105]

number

[0106] Flux operator φ for the "+ mode" of the coupler c+ is expressed by the following equation 7.

[0107]

number

[0108] The flux operator φ for the "-mode" of the coupler c- is expressed by the following equation 8.

[0109]

number

[0110] In the seventh and eighth equations, φ c1 is the flux operator for the portion of the third nonlinear element 50C including the first Josephson junction 21. 7 Formula and 8 In the formula, φ c2 is the flux operator for the portion of the third nonlinear element 50C including the second Josephson junction 22.

[0111] On the right-hand side of the fourth equation above, the signs of the first and second terms are swapped. This cancels out the coupling between quantum bits via the ± modes.

[0112] In the above equation 5, the first and second terms on the right side correspond to the "+ mode." In equation 5, the third to sixth terms on the right side correspond to the "- mode." The "+ mode" corresponds to an LC resonator. In the "- mode," the frequency is variable depending on the magnetic flux Φ.

[0113] Thus, in this embodiment, two modes, "+ mode" and "- mode", exist simultaneously in the coupler. By utilizing the "- mode", a variable frequency can be obtained.

[0114] For simplicity, the above description is given assuming that the first capacitor 11 and the second capacitor 12 have the same value (C). For simplicity, the above description is given assuming that the third capacitor 13 and the fourth capacitor 14 have the same value (C c) is described. In the embodiment, the capacitor of the first capacitor 11 may be different from the capacitor of the second capacitor 12. In the embodiment, the capacitor of the third capacitor 13 may be different from the capacitor of the fourth capacitor 14.

[0115] FIG. 22 is a schematic plan view illustrating the electronic circuit according to the first embodiment. As shown in FIG. 22 , an electronic circuit 130 according to the embodiment includes a plurality of quantum bits 50b and a plurality of couplers 50c. The quantum bits 50b are arranged, for example, in a matrix on the XY plane. One of the plurality of couplers 50c is arranged between one of the quantum bits 50b and another of the quantum bits 50b. One of the quantum bits 50b is, for example, a first nonlinear element 50A. Another of the quantum bits 50b is, for example, a second nonlinear element 50B. One of the plurality of couplers 50c is, for example, a third nonlinear element 50C. One of the plurality of couplers 50c can be coupled (e.g., capacitively coupled) to one of the quantum bits 50b. One of the plurality of couplers 50c can be coupled (e.g., capacitively coupled) to another of the quantum bits 50b. A computing device 230 according to the embodiment includes the electronic circuit 130. The electronic circuit 130 can have the same configuration as the electronic circuits 110 to 117 and 120. For example, Josephson junctions included in the plurality of quantum bits 50b (e.g., first element Josephson junction 51 and second element Josephson junction 52) are provided on the first face F1. Josephson junction circuits 53 included in each of the plurality of couplers 50c are provided on the second face F2.

[0116] (Second embodiment) 23(a), 23(b), 24(a), 24(b), 25(a), and 25(b) are schematic plan views illustrating the electronic circuit according to the second embodiment. The electronic circuit 140 according to the embodiment has first to sixth faces F1 to F6. The configuration described with reference to FIG. 6 may be applied to the first to sixth faces F1 to F6. The first face F1 is one face (e.g., the top face) of the first substrate 81. The second face F2 is another face (e.g., the bottom face) of the first substrate 81. The second face F2 is spaced apart from the first face F1 in a first direction intersecting the first face F1 and is aligned with the first face F1. The third face F3 is one face (e.g., the top face) of the second substrate 82. The fourth face F4 is another face (e.g., the bottom face) of the second substrate 82. The fourth face F4 faces the first face F1. The fourth face F4 is located between the first face F1 and the third face F3. The fifth face F5 is one face (e.g., the top face) of the third substrate 83. The sixth surface F6 is another surface (for example, the bottom surface) of the third substrate 83. The fifth surface F5 faces the second surface F2. The fifth surface F5 is located between the sixth surface F6 and the second surface F2.

[0117] The electronic circuit 140 includes a first nonlinear element 50A, a second nonlinear element 50B, and a third nonlinear element 50C. C The first nonlinear element 50A includes a first element Josephson Joining 51. As shown in FIG. 23(a), the first element Josephson Joining The second nonlinear element 50B is a Josephson type. Joining 52. As shown in FIG. 23(b), the second element Josephson Joining 52 is provided on the second surface F2.

[0118] The third nonlinear element 50C includes a Josephson junction circuit 53. The third nonlinear element 50C can be coupled to the first nonlinear element 50A. The third nonlinear element 50C can be coupled to the second nonlinear element 50B.

[0119] Connections are also made easier in the electronic circuit 140. For example, crosstalk between wiring can be reduced. Scalability is improved. An electronic circuit and a computing device with improved characteristics can be provided. For example, gate operation of quantum bits becomes stable. For example, the stability of quantum bits is improved. The computing device 240 according to the embodiment includes the electronic circuit 140 and a control unit 70.

[0120] In the example of the electronic circuit 140, at least a portion of the Josephson junction circuit 53 is provided on one of the first face F1 and the second face F2. In this example, the Josephson junction circuit 53 is provided on the second face F2.

[0121] In the electronic circuit 140, the configuration of the electronic circuit according to the first embodiment may be applied to the configuration other than the above.

[0122] As shown in Fig. 23(a), in this example, a first element resonator 51O and a first element terminal 51T are provided on the first surface F1. As shown in Fig. 23(b), in this example, a second element resonator 52O and a second element terminal 52T are provided on the second surface F2. As shown in Fig. 24(a), in this example, a first opposing electrode 51C and a first control terminal 51NT are provided on the third surface F3. As shown in Fig. 24(b), in this example, a first readout electrode 51R and a first control electrode 51N are provided on the fourth surface F4.

[0123] As shown in FIG. 25(a), in this example, a second opposing electrode 52C, a second control terminal 52NT, and a first control conductive member 61 are provided on the fifth face F5. As shown in FIG. 25(b), in this example, a second readout electrode 52R and a second control electrode 52N are provided on the sixth face F6. The first control conductive member 61 is connected to the control unit 70 via a first control conductive portion 61u and a second control conductive portion 61v (see FIG. 25(b)). The second readout electrode 52R is connected to the control unit 70.

[0124] 26(a), 26(b), 27(a), 27(b), 28(a), and 28(b) are schematic plan views illustrating the electronic circuit according to the second embodiment. As shown in FIG. 26(a), in an electronic circuit 141 according to the embodiment, a first element is a Josephson Joining 51 is provided on the first face F1. As shown in FIG. 26(b), the second element Josephson Joining26(b), in this example, the Josephson junction circuit 53 is provided on the second surface F2. As shown in FIG. 27(a), the first element resonator 51O, the first element terminal 51T, the first counter electrode 51C, and the first control terminal 51NT are provided on the third surface F3. As shown in FIG. 27(b), the first readout electrode 51R and the first control electrode 51N are provided on the fourth surface F4.

[0125] As shown in FIG. 28(a), the second element resonator 52O, the second element terminal 52T, the second opposing electrode 52C, the second control terminal 52NT, and the first control conductive member 61 are provided on the fifth face F5. As shown in FIG. 28(b), the second readout electrode 52R and the second control electrode 52N are provided on the sixth face F6. The first control conductive member 61 is connected to the control unit 70 via the first control conductive portion 61u and the second control conductive portion 61v (see FIG. 28(b)). The second readout electrode 52R is connected to the control unit 70.

[0126] 29(a) and 29(b) are schematic plan views illustrating the electronic circuit according to the second embodiment. FIG. 30 is a schematic cross-sectional view illustrating an electronic circuit according to the second embodiment. Fig. 29(b) is a transparent plan view. Fig. 29(a) and Fig. 29(b) conceptually show coupling (e.g., capacitive coupling). Fig. 30 is a cross-sectional view taken along line Z1-Z2 of Fig. 29(a) and Fig. 29(b). As shown in FIG. 29(a), an electronic circuit 150 according to the embodiment includes first nonlinear elements 50A (e.g., multiple quantum bits). In this example, the multiple first nonlinear elements 50A are arranged in a matrix along a first surface F1 that is aligned with the XY plane. As shown in FIG. 29(a), multiple couplers 50c may be provided on the first surface F1. One of the multiple couplers 50c provided on the first surface F1 may couple one of the multiple first nonlinear elements 50A to another of the multiple first nonlinear elements 50A. In FIG. 29(a), the dashed line connecting one of the multiple couplers 50c and one of the multiple first nonlinear elements 50A corresponds to capacitive coupling.

[0127] As shown in FIG. 29(b), the electronic circuit 150 includes a plurality of second nonlinear elements 50B (e.g., a plurality of quantum bits). In this example, the plurality of second nonlinear elements 50B are arranged in a matrix along a second surface F2 that is aligned with the XY plane, for example. As shown in FIG. 29(b), a plurality of couplers 50c may be provided on the second surface F2. One of the plurality of couplers 50c provided on the second surface F2 may couple one of the plurality of second nonlinear elements 50B to another of the plurality of second nonlinear elements 50B. In FIG. 29(b), the dashed line connecting one of the plurality of couplers 50c to one of the plurality of second nonlinear elements 50B corresponds to capacitive coupling.

[0128] As shown in Fig. 29(b), the electronic circuit 150 includes a third nonlinear element 50C (coupler). In this example, a plurality of third nonlinear elements 50C are provided. In this example, the third nonlinear elements 50C are provided on the second face F2. In an embodiment, the third nonlinear element 50C may be provided on the first face F1.

[0129] As already described, the first nonlinear element 50A includes a first element Josephson junction 51 (see FIG. 30). The second nonlinear element 50B includes a second element Josephson junction 52 (see FIG. 30). The third nonlinear element 50C includes a Josephson junction circuit 53 (see FIG. 30). As already described, the Josephson junction circuit 53 may include a first Josephson junction 21, a second Josephson junction 22, a third Josephson junction 23, etc.

[0130] 30, the first-element Josephson junction 51 is provided on the first face F1. The second-element Josephson junction 52 is provided on the second face F2. The second face F2 is spaced apart from the first face F1 in a first direction D1 (e.g., the Z-axis direction) that intersects with the first face F1 and is aligned with the first face F1. In this example, the first face F1 is one face (e.g., the top face) of the first substrate 81. The second face F2 is another face (e.g., the bottom face) of the first substrate 81.

[0131] The third nonlinear element 50C can be coupled to the first nonlinear element 50A, and the third nonlinear element 50C can be coupled to the second nonlinear element 50B. At least a portion of the Josephson junction circuit 53 is provided on one of the first face F1 and the second face F2. In this example, the Josephson junction circuit 53 is provided on the second face F2.

[0132] The electronic circuit 150 can also provide an electronic circuit and a computing device with improved performance. total The computing device 250 includes the electronic circuit 150 described above.

[0133] In the electronic circuit 150, for example, the Josephson junction circuit 53 can be coupled to the first element Josephson junction 51. For example, the Josephson junction circuit 53 can be coupled to the second element Josephson junction 52.

[0134] As shown in FIG. 30, in this example, at least a part of the first-element Josephson junction 51 overlaps with the second-element Josephson junction 52 in the first direction D1 (for example, the Z-axis direction). child In the circuit 150, for example, a first-element Josephson junction 51 provided on the first face F1 may be coupled to the second-element Josephson junction 52 closest to the first-element Josephson junction 51 among a plurality of second-element Josephson junctions 52 provided on the second face F2.

[0135] In this example, one of the plurality of second-element Josephson junctions 52 overlaps one of the plurality of first-element Josephson junctions 51 in the first direction D1 (e.g., the Z-axis direction). The one of the plurality of second-element Josephson junctions 52 is coupled to the one of the plurality of first-element Josephson junctions 51 by the third nonlinear element 50C.

[0136] In this example, a connecting member 58v is provided. The connecting member 58v extends through the first substrate 81 along the first direction D1. The connecting member 58v couples the first-element Josephson junction 51 provided on the first face F1 to the third nonlinear element 50C (Josephson junction circuit 53) provided on the second face F2. The third nonlinear element 50C (Josephson junction circuit 53) provided on the second face F2 is coupled to the second-element Josephson junction 52 provided on the second face F2.

[0137] In an embodiment, the first-element Josephson junction 51 located on the first face F1 may be coupled to a second-element Josephson junction 52 that is not closest to the first-element Josephson junction 51 among a plurality of second-element Josephson junctions 52 located on the second face F2. For example, as described below, the first-element Josephson junction 51 located on the first face F1 may be coupled to a second-element Josephson junction 52 that is third closest (or more) to the first-element Josephson junction 51 among a plurality of second-element Josephson junctions 52 located on the second face F2.

[0138] FIG. 31 is a schematic cross-sectional view illustrating an electronic circuit according to the second embodiment. 31, in an electronic circuit 151 according to the embodiment, a plurality of second-element Josephson junctions 52 are provided on a second plane F2. The direction from one of the plurality of second-element Josephson junctions 52 (second-element Josephson junction 52a) to another of the plurality of second-element Josephson junctions 52 (second-element Josephson junction 52b) is along a second direction D2. The second direction D2 intersects with the first direction D1 (for example, the Z-axis direction).

[0139] The Josephson junction circuit 53 included in the third nonlinear element 50C is coupled to one (second-element Josephson junction 52a) of the multiple second-element Josephson junctions 52. As already explained, the Josephson junction circuit 53 is coupled to the first-element Josephson junction 51. The coupling is capacitive. In this example, the Josephson junction circuit 53 is coupled to the first-element Josephson junction 51 via a wiring 58L (conductive member) and a connection member 58v. The position of another one (second-element Josephson junction 52b) of the multiple second-element Josephson junctions 52 in the second direction D2 is between the position of the first-element Josephson junction 51 in the second direction D2 and the position of the one (second-element Josephson junction 52a) of the multiple second-element Josephson junctions 52 in the second direction D2.

[0140] That is, in the electronic circuit 151, the first-element Josephson junction 51 is coupled to a second-element Josephson junction 52 that is third (or more) closest to the first-element Josephson junction 51 among the plurality of second-element Josephson junctions 52. Another second-element Josephson junction 52 may be present between one of the plurality of second-element Josephson junctions 52 coupled to the first-element Josephson junction 51 and the first-element Josephson junction 51. The computing device 251 includes the electronic circuit 151 described above.

[0141] FIG. 32 is a schematic cross-sectional view illustrating an electronic circuit according to the second embodiment. 32, in an electronic circuit 152 according to the embodiment, a first-element Josephson junction 51 and one of a plurality of second-element Josephson junctions 52 (second-element Josephson junction 52a) are coupled by a Josephson junction circuit 53. The coupling is capacitive coupling. The coupling is performed, for example, via a wiring 59L and a connection member 58L. A plurality of second-element Josephson junctions 52 (a plurality of second-element Josephson junctions 52b) may be provided between the first-element Josephson junction 51 and one of the plurality of second-element Josephson junctions 52. A computing device 252 includes the electronic circuit 152 described above.

[0142] 30 to 32, the dashed line connecting the first element Josephson junction 51 and the connecting member 58v corresponds to capacitive coupling, and the dashed line connecting the second element Josephson junction 52 and the Josephson junction circuit 53 corresponds to capacitive coupling.

[0143] In the electronic circuits 140, 141, and 150 to 152, the configurations described in relation to the first embodiment may be applied to the extent technically possible.

[0144] FIG. 33 is a schematic diagram illustrating an electronic circuit and a computing device according to the embodiment. 33 , in an electronic circuit 160 according to the embodiment, a Josephson junction circuit 53 includes a first inductor 31, a second inductor 32, and a third Josephson junction 23. A third nonlinear element 50C further includes a first conductive member 25a, a second conductive member 25b, and a third conductive member 25c. The first conductive member 25a connects the first inductor 31 to the third Josephson junction 23. The second conductive member 25b connects the second inductor 32 to the third Josephson junction 23. The third conductive member 25c connects the first inductor 31 to the second inductor 32. These connections may be, for example, electrical connections.

[0145] For example, the first conductive member 25a connects one end 31e of the first inductor 31 to one end 23e of the third Josephson junction 23. The second conductive member 25b connects one end 32e of the second inductor 32 to the other end 23f of the third Josephson junction 23. The third conductive member 25c connects the other end 31f of the first inductor 31 to the other end 32f of the second inductor 32.

[0146] In the electronic circuit 160, the third Josephson junction 23 is provided on the second face F2. The first inductor 31 and the second inductor 32 may be provided on the second face F2. The configuration of the electronic circuit 160 may be the same as the configurations described for the electronic circuits 110 to 117, 120, 130, 140, 141, and 150 to 152. The computing device 260 includes the electronic circuit 160 described above.

[0147] (Third embodiment) The third embodiment relates to a method for manufacturing an electronic circuit. 34(a) to 34(i) are schematic cross-sectional views illustrating a method for manufacturing an electronic circuit according to the third embodiment. 34(a), a first substrate 81 is prepared. The first substrate 81 includes a first surface F1 and a second surface F2.

[0148] As shown in FIG. 34(b), a conductive portion 85 is formed on the first substrate 81. The conductive portion 85 extends along a first direction (Z-axis direction) from the second surface F2 to the first surface F1. The conductive portion 85 may be a TSV or the like. The conductive portion 85 may be a first element conductive portion 51v and a second element conductive portion 52v or the like.

[0149] 34(c), a conductive member 86a is formed on the first surface F1. The conductive member 86a may be at least a part of a capacitor included in the first nonlinear element 50A, the second nonlinear element 50B, etc. At least a part of the conductive member 86a is electrically connected to the conductive portion 85.

[0150] 34(d), a first-element Josephson junction 51 and a second-element Josephson junction 52 are formed on the first surface F1. In this manner, a first nonlinear element 50A and a second nonlinear element 50B are formed on the first surface F1 of the first substrate 81. The first nonlinear element 50A includes the first-element Josephson junction 51. The second nonlinear element 50B includes the second-element Josephson junction 52.

[0151] As shown in FIG. 34(e), a first member 88 including a recess 88d is prepared. As shown in FIG. 33(f), a first member 88 is provided. The first nonlinear element 50A and the second nonlinear element 50B are located between the first substrate 81 and the recess 88d. A support portion 88s may be provided between the first surface F1 and the recess 88d. The support portion 88s stabilizes the distance between the first surface F1 and the recess 88d.

[0152] 34(g), a conductive member 86b is formed on the second surface F2. The conductive member 86b may be at least a part of a capacitor included in the third nonlinear element 50C, etc. At least a part of the conductive member 86b is electrically connected to the conductive portion 85.

[0153] 34(h), the first Josephson junction 21, the second Josephson junction 22, and the third Josephson junction 23 are formed on the second surface F2. These Josephson junctions are included in the Josephson junction circuit 53 of the third nonlinear element 50C. In this manner, in this manufacturing method, the third nonlinear element 50C including the Josephson junction circuit 53 is formed on the second surface F2 of the first substrate 81. The first surface F1 is located between the second surface F2 and the first member 88.

[0154] 34(i), the first member 88 is removed, thereby obtaining, for example, an electronic circuit 110.

[0155] 35(a) to 35(i) are schematic cross-sectional views illustrating a method for manufacturing an electronic circuit according to the third embodiment. As shown in Fig. 35(a), a substrate that will become first substrate 81 is prepared. As shown in Fig. 35(b), a recess 81d is formed on a first surface F1 of first substrate 81. First substrate 81 includes a second surface F2. First substrate 81 includes a protrusion 81p around recess 81d.

[0156] As shown in FIG. 35(c), a conductive portion 85 is formed on the first substrate 81. The conductive portion 85 extends along a first direction (Z-axis direction) from the second surface F2 to the first surface F1. The conductive portion 85 may be a TSV or the like. The conductive portion 85 may be a first element conductive portion 51v and a second element conductive portion 52v or the like.

[0157] 35(d), a conductive member 86a is formed on the first surface F1. The conductive member 86a may be at least a part of a capacitor included in the first nonlinear element 50A, the second nonlinear element 50B, etc. At least a part of the conductive member 86a is electrically connected to the conductive portion 85.

[0158] 35(e), a first-element Josephson junction 51 and a second-element Josephson junction 52 are formed on the first surface F1. In this manner, a first nonlinear element 50A and a second nonlinear element 50B are formed on the first surface F1 of the first substrate 81. The first nonlinear element 50A includes the first-element Josephson junction 51. The second nonlinear element 50B includes the second-element Josephson junction 52.

[0159] 35(f), a first member 88 is provided. The first nonlinear element 50A and the second nonlinear element 50B are located between the first substrate 81 and the first member 88. A support portion 88s may be provided between the recess 81d on the first surface F1 and the first member 88. The support portion 88s stabilizes the distance between the recess 81d and the first member 88.

[0160] 35(g), a conductive member 86b is formed on the second surface F2. The conductive member 86b may be at least a part of a capacitor included in the third nonlinear element 50C, etc. At least a part of the conductive member 86b is electrically connected to the conductive portion 85.

[0161] 35(h), a first Josephson junction 21, a second Josephson junction 22, and a third Josephson junction 23 are formed on the second surface F2. These Josephson junctions are included in the Josephson junction circuit 53 of the third nonlinear element 50C. In this manner, in this manufacturing method, the third nonlinear element 50C including the Josephson junction circuit 53 is formed on the second surface F2 of the first substrate 81. The first surface F1 is located between the second surface F2 and the first member 88.

[0162] 35(i), the first member 88 is removed. Furthermore, the protrusion 81p of the first substrate 81 is removed. As a result, for example, an electronic circuit 110 is obtained.

[0163] The embodiment may include the following configurations (technical solutions). (Configuration 1) a first nonlinear element including a first element Josephson junction provided in the first region of a first surface including the first region and the second region; a second nonlinear element including a second element Josephson junction provided in the second region; a third nonlinear element including a Josephson junction circuit, at least a portion of the Josephson junction circuit being provided on a second surface, the second surface being spaced apart from the first surface along the first surface in a first direction intersecting the first surface, the third nonlinear element being couplable with the first nonlinear element, and the third nonlinear element being couplable with the second nonlinear element; An electronic circuit comprising:

[0164] (Configuration 2) Further comprising a first substrate; the first surface is one surface of the first substrate, 2. The electronic circuit of claim 1, wherein the second surface is another surface of the first substrate.

[0165] (Configuration 3) the Josephson junction circuit includes a first Josephson junction, a second Josephson junction, and a third Josephson junction; the third nonlinear element further includes a first conductive member, a second conductive member, and a third conductive member; the first conductive member connects one end of the first Josephson junction to one end of the third Josephson junction; The second conductive member connects one end of the second Josephson junction to the other end of the third Josephson junction. end and connect to The third conductive member connects the other end of the first Josephson junction to the other end of the second Josephson junction. end and connect to the first Josephson junction, the second Josephson junction, the third Josephson junction, the first conductive member, the second conductive member, and the third conductive member form a loop, the first nonlinear element is coupleable to the first conductive member; 3. The electronic circuit of claim 1, wherein the second nonlinear element is couplable with the second conductive member.

[0166] (Configuration 4) a first element conductive portion extending in the first direction through the first substrate; the first element conductive portion is electrically connected to the first nonlinear element or is capable of being coupled to the first nonlinear element; 4. The electronic circuit of claim 3, wherein the first element conductive portion is electrically connected to the first conductive member or is couplable with the first conductive member.

[0167] (Configuration 5) a second element conductive portion extending in the first direction through the first substrate; the second element conductive portion is electrically connected to the second nonlinear element or is capable of being coupled to the second nonlinear element; 5. The electronic circuit of claim 3, wherein the second element conductive portion is electrically connected to the second conductive member or is connectable to the second conductive member.

[0168] (Configuration 6) a first element resonator that can be coupled to the first nonlinear element; a first element terminal that can be coupled to the first element resonator; 6. The electronic circuit according to any one of configurations 3 to 5, further comprising:

[0169] (Configuration 7) The electronic circuit of configuration 6, wherein at least one of at least a portion of the first element resonator, at least a portion of the first element terminal, at least a portion of the second element resonator, and at least a portion of the second element terminal is provided on the first surface.

[0170] (Configuration 8) a second substrate including a third surface and a fourth surface, the fourth surface facing the first surface; the second substrate, wherein the fourth surface is between the first surface and the third surface; a first opposing electrode provided on the fourth surface; a second opposing electrode provided on the fourth surface; Furthermore, the first counter electrode is connectable to the first element terminal; 8. The electronic circuit of claim 7, wherein the second counter electrode is couplable to the second element terminal.

[0171] (Configuration 9) a first readout electrode provided on the third surface; a first readout conductive portion extending in the first direction through the second substrate and electrically connecting the first counter electrode to the first readout electrode; 9. The electronic circuit of claim 8, further comprising:

[0172] (Configuration 10) a third substrate including a fifth surface and a sixth surface, the fifth surface facing the second surface and the fifth surface being between the sixth surface and the second surface; a magnetic flux control unit provided on the fifth surface and capable of controlling a magnetic flux in a space within the loop; 10. The electronic circuit of claim 8 or 9, further comprising:

[0173] (Configuration 11) a third substrate including a fifth surface and a sixth surface, the fifth surface facing the second surface and the fifth surface being between the sixth surface and the second surface; a first control conductive member provided on the fifth surface; a first control conductive portion extending in the first direction through the third substrate and electrically connected to a portion of the first control conductive member; The electronic circuit according to any one of configurations 1 to 9, further comprising:

[0174] (Configuration 12) a first substrate; A second substrate; Furthermore, the first surface is one surface of the first substrate, 2. The electronic circuit of claim 1, wherein the second surface is one surface of the second substrate.

[0175] (Configuration 13) a first nonlinear element including a first element Josephson junction disposed on the first surface; a second nonlinear element including a second element Josephson junction provided on a second surface, the second surface being spaced apart from the first surface and extending along the first surface in a first direction intersecting the first surface; a third nonlinear element including a Josephson junction circuit, the third nonlinear element being couplable with the first nonlinear element and the third nonlinear element being couplable with the second nonlinear element; An electronic circuit comprising:

[0176] (Configuration 14) 14. The electronic circuit of claim 13, wherein at least a portion of the Josephson junction circuit is provided on one of the first surface and the second surface.

[0177] (Configuration 15) the Josephson junction circuit is couplable with a first element Josephson junction; the Josephson junction circuit is coupleable with a second element Josephson junction; a plurality of said second element Josephson junctions are provided on said second surface; a direction from one of the plurality of second-element Josephson junctions to another of the plurality of second-element Josephson junctions along a second direction that intersects the first direction; the third element Josephson junction is couplable with one of the plurality of second element Josephson junctions; 15. The electronic circuit of structure 13 or 14, wherein the position of another one of the plurality of second-element Josephson junctions in the second direction is between the position of the first-element Josephson junction in the second direction and the position of the one of the plurality of second-element Josephson junctions in the second direction.

[0178] (Configuration 16) the Josephson junction circuit includes a first Josephson junction, a second Josephson junction, and a third Josephson junction; the third nonlinear element further includes a first conductive member, a second conductive member, and a third conductive member; the first conductive member connects one end of the first Josephson junction to one end of the third Josephson junction; the second conductive member connects one end of the second Josephson junction to the other end of the third Josephson junction; the third conductive member connects the other end of the first Josephson junction to the other end of the second Josephson junction; the first Josephson junction, the second Josephson junction, the third Josephson junction, the first conductive member, the second conductive member, and the third conductive member form a loop, the first nonlinear element is coupleable to the first conductive member; 16. The electronic circuit according to any one of configurations 13 to 15, wherein the second nonlinear element is connectable to the second conductive member.

[0179] (Configuration 17) the Josephson junction circuit includes a first inductor, a second inductor, and a third Josephson junction; the third nonlinear element further includes a first conductive member, a second conductive member, and a third conductive member; the first conductive member connects one end of the first inductor to one end of the third Josephson junction; The second conductive member connects one end of the second inductor to the other end of the third Josephson junction. end and connect to The third conductive member connects the other end of the first inductor to the other end of the second inductor. end and connect to the first Josephson junction, the second Josephson junction, the third Josephson junction, the first conductive member, the second conductive member, and the third conductive member form a loop, the first nonlinear element is coupleable to the first conductive member; 14. The electronic circuit of claim 1 or 13, wherein the second nonlinear element is couplable with the second conductive member.

[0180] (Configuration 18) 18. The electronic circuit according to any one of configurations 1 to 17, further comprising a first control terminal to which a first control signal for controlling the first nonlinear element can be applied.

[0181] (Configuration 19) 18. The electronic circuit according to any one of configurations 3 to 9, 16, and 17, further comprising a magnetic flux control unit capable of controlling the magnetic flux in the space within the loop.

[0182] (Configuration 20) an electronic circuit according to configuration 10 or 19; A control unit; Equipped with the magnetic flux control unit includes a first control conductive unit, The control unit is capable of providing a flux control signal to the first control conductive unit.

[0183] (Configuration 21) 21. The computing device of claim 20, wherein a coupling strength between the first nonlinear element and the second nonlinear element varies depending on the magnetic flux in the space.

[0184] (Configuration 22) the third nonlinear element is capable of resonating in a plurality of modes; 22. The computing device of claim 20 or 21, wherein the resonant frequency in each of the plurality of modes is higher than the resonant frequency of the first nonlinear element, higher than the resonant frequency of the second nonlinear element, and lower than the sum of the resonant frequency of the first nonlinear element and the resonant frequency of the second nonlinear element.

[0185] (Configuration 23) The control unit is capable of performing at least a first operation and a second operation, In the first operation, the control unit performs two-qubit operations on the first nonlinear element and the second nonlinear element by changing the magnetic flux between a first value and a second value different from the first value; 23. The computing device according to any one of configurations 20 to 22, wherein in the second operation, the control unit performs the two-qubit operation of the first nonlinear element and the second nonlinear element by modulating the magnetic flux with an alternating current.

[0186] (Configuration 24) forming a first nonlinear element and a second nonlinear element on a first surface of a first substrate, the first nonlinear element including a first element Josephson junction, and the second nonlinear element including a second element Josephson junction; a first member including a recess, the first nonlinear element and the second nonlinear element being located between the first substrate and the recess; A method for manufacturing an electronic circuit, wherein a third nonlinear element including a Josephson junction circuit is formed on a second surface of the first substrate, and the first surface is between the second surface and the first member.

[0187] (Configuration 25) forming a first nonlinear element and a second nonlinear element in a recessed portion of a first surface of a first substrate, the first nonlinear element including a first element Josephson junction, and the second nonlinear element including a second element Josephson junction; a first member is provided, and the first nonlinear element and the second nonlinear element are disposed between the first substrate and the first member; A method for manufacturing an electronic circuit, wherein a third nonlinear element including a Josephson junction circuit is formed on a second surface of the first substrate, and the first surface is between the second surface and the first member.

[0188] According to the embodiment, an electronic circuit and a computing device that can improve controllability can be provided.

[0189] The embodiments of the present invention have been described above with reference to examples. However, the present invention is not limited to these examples. For example, the specific configurations of elements such as nonlinear elements, Josephson junctions, capacitors, and conductive members included in electronic circuits or computing devices are within the scope of the present invention as long as a person skilled in the art can implement the present invention in a similar manner and obtain similar effects by appropriately selecting them from known ranges.

[0190] 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 encompasses the gist of the present invention.

[0191] All electronic circuits and computing devices that can be implemented by a person skilled in the art by appropriately modifying the design based on the electronic circuits and computing devices described above as embodiments of the present invention also fall within the scope of the present invention, as long as they include the gist of the present invention.

[0192] 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.

[0193] Although several 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 embodied 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 within the scope and spirit of the invention, and are also included in the scope of the invention and its equivalents as defined in the claims. [Explanation of symbols]

[0194] 11-15...first to fifth capacitors, 11u, 11v, 12u, 12v...conductive members, 21-23...first to third Josephson junctions, 21e-23e...one end, 21f-23f...other end, 25a-25c...first to third conductive members, 26a-26f...conductive films, 26i-26k...insulating films, 31, 32...first and second inductors, 31e, 32e...one end, 31f, 32f...other end, 41, 42...first and second element capacitors, 50A, 50B, 50C...first to third nonlinear elements, 50D-50I...nonlinear elements, 50b...qubit, 50c...coupler, 50r...loop, 51, 52...first and second element Josephson junctions, 51C, 52C...first and second opposing electrodes, 51N, 52N...first and second control electrodes, 51NT, 52NT...first and second control terminals, 51Nv, 52Nv...conductive portion, 51O, 52O...first and second element resonators, 51R, 52R...first and second readout electrodes, 51Rv, 52Rv...conductive portion, 51T, 52T...first and second element terminals, 51v, 52v...first and second element conductive portion, 52a, 52b...second element Josephson junction, 53...Josephson junction circuit, 55a to 55d...conductive film, 55i, 55j...insulating film, 55u, 55v...conductive member, 58L...wiring, 58a, 58b...connecting portion, 58v...connecting member, 60...magnetic flux control portion, 61...first control conductive member, 61i...control current, 61u, 61v...first and second control conductive portions, 70...control unit, 81-83...first to third substrates, 81C-83C, 81D-83D...connection portion, 81a, 81b...first and second regions, 81d...recess, 81p...protrusion, 85...conductive portion, 86a, 86b...conductive member, 88...first member, 88d...recess, 88s...support portion, Φ...magnetic flux, θ1, θ2...gate rotation angle, 110-117, 120, 130, 140, 141, 150-152, 160...electronic circuit, 210-217, 220, 230, 240, 241, 250-252, 260...computing device, CS1, CSZZ...coupling strength, D1, D2...first and second directions, F1~F6...first to sixth planes, FT1...fidelity, GND...ground potential, MF1...magnetic flux, Mv1...first magnetic flux value, SP...space, ST1, ST2...first and second states, Sc1, Sc2...first and second control signals, fb1~fb3...resonance frequency, fc1, fc2, fo1...frequency

Claims

1. a first nonlinear element including a first element Josephson junction provided in the first region of a first surface including the first region and the second region; a second nonlinear element including a second element Josephson junction provided in the second region; a third nonlinear element including a Josephson junction circuit, at least a portion of the Josephson junction circuit being provided on a second surface, the second surface being spaced apart from the first surface along the first surface in a first direction intersecting the first surface, the third nonlinear element being couplable with the first nonlinear element, and the third nonlinear element being couplable with the second nonlinear element; Equipped with the Josephson junction circuit includes a first Josephson junction, a second Josephson junction, and a third Josephson junction; the third nonlinear element further includes a first conductive member, a second conductive member, and a third conductive member; the first conductive member connects one end of the first Josephson junction to one end of the third Josephson junction; the second conductive member connects one end of the second Josephson junction to the other end of the third Josephson junction; the third conductive member connects the other end of the first Josephson junction to the other end of the second Josephson junction; the first Josephson junction, the second Josephson junction, the third Josephson junction, the first conductive member, the second conductive member, and the third conductive member form a loop, the first nonlinear element is coupleable to the first conductive member; The second nonlinear element is couplable with the second conductive member.

2. Further comprising a first substrate; the first surface is one surface of the first substrate, The electronic circuit of claim 1 , wherein the second surface is another surface of the first substrate.

3. a first element conductive portion extending in the first direction through the first substrate; the first element conductive portion is electrically connected to the first nonlinear element or is capable of being coupled to the first nonlinear element; The electronic circuit according to claim 2 , wherein the first element conductive portion is electrically connected to the first conductive member or is connectable to the first conductive member.

4. a first element resonator that can be coupled to the first nonlinear element; a first element terminal that can be coupled to the first element resonator; a second element resonator that can be coupled to the second nonlinear element; a second element terminal that can be coupled to the second element resonator; The electronic circuit according to any one of claims 1 to 3, further comprising:

5. 5. The electronic circuit according to claim 4, wherein at least one of at least a portion of the first element resonator, at least a portion of the first element terminal, at least a portion of the second element resonator, and at least a portion of the second element terminal is provided on the first surface.

6. a second substrate including a third surface and a fourth surface, the fourth surface facing the first surface; the second substrate, the fourth surface being between the first surface and the third surface; a first opposing electrode provided on the fourth surface; a second opposing electrode provided on the fourth surface; Furthermore, the first counter electrode is connectable to the first element terminal; The electronic circuit of claim 5 , wherein the second counter electrode is couplable with the second element terminal.

7. a third substrate including a fifth surface and a sixth surface, the fifth surface facing the second surface and the fifth surface being between the sixth surface and the second surface; a magnetic flux control unit provided on the fifth surface and capable of controlling a magnetic flux in a space within the loop; The electronic circuit of claim 6 further comprising:

8. 7. The electronic circuit according to claim 1, further comprising a magnetic flux control unit capable of controlling magnetic flux in the space within the loop.

9. an electronic circuit according to claim 7 or 8; A control unit; Equipped with the magnetic flux control unit includes a first control conductive unit, The controller is capable of providing a flux control signal to the first control conductive section.

10. the control unit is capable of performing at least a first operation and a second operation; In the first operation, the control unit performs two-qubit operations on the first nonlinear element and the second nonlinear element by changing the magnetic flux between a first value and a second value different from the first value; The computing device according to claim 9 , wherein in the second operation, the control unit performs the two-qubit operation of the first nonlinear element and the second nonlinear element by modulating the magnetic flux with an alternating current.

11. A method for manufacturing an electronic circuit, the electronic circuit comprising: a first nonlinear element including a first element Josephson junction provided in the first region of a first surface including the first region and the second region; a second nonlinear element including a second element Josephson junction provided in the second region; a third nonlinear element including a Josephson junction circuit, at least a portion of the Josephson junction circuit being provided on a second surface, the second surface being spaced apart from the first surface along the first surface in a first direction intersecting the first surface, the third nonlinear element being couplable with the first nonlinear element, and the third nonlinear element being couplable with the second nonlinear element; Equipped with the Josephson junction circuit includes a first Josephson junction, a second Josephson junction, and a third Josephson junction; the third nonlinear element further includes a first conductive member, a second conductive member, and a third conductive member; the first conductive member connects one end of the first Josephson junction to one end of the third Josephson junction; the second conductive member connects one end of the second Josephson junction to the other end of the third Josephson junction; the third conductive member connects the other end of the first Josephson junction to the other end of the second Josephson junction; the first Josephson junction, the second Josephson junction, the third Josephson junction, the first conductive member, the second conductive member, and the third conductive member form a loop, the first nonlinear element is coupleable to the first conductive member; the second nonlinear element is coupleable to the second conductive member; forming the first nonlinear element and the second nonlinear element on the first surface of a first substrate, the first nonlinear element including the first element Josephson junction, and the second nonlinear element including the second element Josephson junction; a first member including a recess, the first nonlinear element and the second nonlinear element being located between the first substrate and the recess; A method for manufacturing an electronic circuit, wherein the third nonlinear element including the Josephson junction circuit is formed on the second surface of the first substrate, and the first surface is between the second surface and the first member.

12. A method for manufacturing an electronic circuit, the electronic circuit comprising: a first nonlinear element including a first element Josephson junction provided in the first region of a first surface including the first region and the second region; a second nonlinear element including a second element Josephson junction provided in the second region; a third nonlinear element including a Josephson junction circuit, at least a portion of the Josephson junction circuit being provided on a second surface, the second surface being spaced apart from the first surface along the first surface in a first direction intersecting the first surface, the third nonlinear element being couplable with the first nonlinear element, and the third nonlinear element being couplable with the second nonlinear element; Equipped with the Josephson junction circuit includes a first Josephson junction, a second Josephson junction, and a third Josephson junction; the third nonlinear element further includes a first conductive member, a second conductive member, and a third conductive member; the first conductive member connects one end of the first Josephson junction to one end of the third Josephson junction; the second conductive member connects one end of the second Josephson junction to the other end of the third Josephson junction; the third conductive member connects the other end of the first Josephson junction to the other end of the second Josephson junction; the first Josephson junction, the second Josephson junction, the third Josephson junction, the first conductive member, the second conductive member, and the third conductive member form a loop, the first nonlinear element is coupleable to the first conductive member; the second nonlinear element is coupleable to the second conductive member; forming the first nonlinear element and the second nonlinear element in a recessed portion of the first surface of a first substrate, the first nonlinear element including the first element Josephson junction, and the second nonlinear element including the second element Josephson junction; a first member is provided, and the first nonlinear element and the second nonlinear element are disposed between the first substrate and the first member; A method for manufacturing an electronic circuit, wherein the third nonlinear element including the Josephson junction circuit is formed on the second surface of the first substrate, and the first surface is between the second surface and the first member.

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