Quantum bit coupling structure and coupling method, electronic equipment and storage medium

Abstract

The invention provides a quantum bit coupling structure, a quantum bit coupling method, electronic equipment and a storage medium. The quantum bit coupling structure is arranged in a quantum device, and comprises a plurality of quantum bits, and the plurality of quantum bits are specifically arranged; the quantum bit coupler is configured to be coupled with quantum bits, and the quantum bit coupler can be bent in the quantum device according to a specific arrangement of the plurality of quantum bits. According to the quantum bit coupling structure, the quantum bit coupler which is bent according to the specific arrangement of the plurality of quantum bits is arranged in the quantum bit coupling structure, so that the long-range coupling between the quantum bits with relatively long spatial distances in the quantum device is realized, and the quantum gate operation between the quantum bits with long distances in the quantum device is further realized.

Description

Technical Field

[0001] This disclosure relates to the field of quantum computing, and provides a coupling structure for qubits, a coupling method for qubits, an electronic device, and a storage medium. Background Technology

[0002] In current quantum processing technologies, qubits are an important implementation method. To achieve quantum entanglement and quantum parallel computing, qubits need to have controllable interactions and a certain coupling strength to effectively execute various quantum gate operations.

[0003] Current technologies primarily focus on coupling between nearby qubits. However, for qubits that are spatially distant, the coupling is extremely weak, making quantum gate operations between qubits very difficult. Therefore, there is an urgent need for a solution that can couple spatially distant qubits. Summary of the Invention

[0004] To address the problems existing in the prior art, this disclosure provides a quantum bit coupling structure, a quantum bit coupling method, an electronic device, and a storage medium for realizing long-range coupling between quantum bits.

[0005] This disclosure provides a coupling structure for qubits disposed in a quantum device, comprising: a plurality of qubits arranged in a specific configuration; and a qubit coupler configured to couple with the qubits, wherein the qubit coupler is capable of bending within the quantum device according to the specific configuration of the plurality of qubits.

[0006] Optionally, the qubit coupler includes a first coupler and a second coupler; wherein the first coupler is configured to couple non-adjacent qubits, and the second coupler is configured to couple adjacent qubits.

[0007] Optionally, the coupling structure further includes a parallel plate capacitor disposed between the qubit and the first coupler, configured to couple the qubit to the first coupler.

[0008] Optionally, the coupling strength between the first coupler and the quantum bit is determined based on coupling parameters, which include at least one of the following: the frequency of the first coupler, the capacitance of the first coupler, and the coupling capacitance between the first coupler and the quantum bit.

[0009] Optionally, the coupling structure further includes two Josephson junctions connected in parallel, which are disposed at one or both ends of the first coupler and configured to adjust the frequency of the first coupler.

[0010] Optionally, the coupling capacitance between the first coupler and the qubit is determined based on the length of the first coupler or the distance between the first coupler and the qubit.

[0011] This disclosure also provides a method for coupling qubits, comprising: obtaining an initial coupling strength between a first qubit and a second qubit; and, when the initial coupling strength satisfies a preset long-range coupling condition, coupling the first qubit and the second qubit long-range through a first coupler in a qubit coupler.

[0012] Optionally, the initial coupling strength satisfying the preset long-range coupling condition includes: determining that the initial coupling strength satisfies the preset long-range coupling condition when the initial coupling strength is less than a first preset strength threshold, wherein the initial coupling strength is the coupling strength when the second coupler in the qubit coupler couples the first qubit with the second qubit.

[0013] Optionally, the coupling method further includes: after long-range coupling of the first qubit and the second qubit through a first coupler in a qubit coupler, obtaining the long-range coupling strength between the first qubit and the second qubit; and adjusting the first coupler to improve the long-range coupling strength when the long-range coupling strength meets a preset adjustment condition.

[0014] Optionally, the long-range coupling strength satisfying the preset adjustment condition includes: determining that the long-range coupling strength satisfies the preset adjustment condition when the long-range coupling strength is less than a second preset strength threshold.

[0015] Optionally, adjusting the first coupler includes adjusting the coupling parameters of the first coupler, wherein the coupling parameters include at least one of the frequency of the first coupler, the capacitance of the first coupler, and the coupling capacitance between the first coupler and the quantum bit.

[0016] This disclosure also provides an electronic device, including: at least one processor; and a memory communicatively connected to the at least one processor; wherein the memory stores instructions executable by the at least one processor, the instructions being executed by the at least one processor to enable the at least one processor to perform the quantum bit coupling method as described above.

[0017] This disclosure also provides a non-transient computer storage medium storing computer instructions, wherein the computer instructions are used to cause the computer to perform the quantum bit coupling method as described above.

[0018] The qubit coupling structure disclosed herein includes a qubit coupler that can be bent according to a specific arrangement of multiple qubits. This allows the coupling structure to perform long-range coupling of qubits that are spatially distant in a quantum device through the qubit coupler. This reduces direct interactions between coupled qubits, thereby reducing crosstalk between qubits during coupling and enabling high-fidelity quantum gate operations between long-distance qubits.

[0019] In the qubit coupling structure provided in this disclosure, the coupling strength between the first coupler and the qubit is determined based on the coupling parameters. Therefore, this disclosure can adjust the coupling strength between the first coupler and the qubit by adjusting at least one of the frequency of the first coupler, the capacitance of the first coupler, and the coupling capacitance between the first coupler and the qubit. This simplifies the process of adjusting the coupling strength between qubits and improves the efficiency of adjusting the coupling strength between qubits.

[0020] The coupling structure of the qubits provided in this disclosure further includes two Josephson junctions disposed at one or both ends of a first coupler. By changing the frequency of the first coupler through the two Josephson junctions disposed at one or both ends, the coupling strength between the qubits can be adjusted by changing the frequency of the first coupler while keeping the state of the qubits unchanged. This simplifies the process of adjusting the coupling strength between the qubits and helps to improve the flexibility and efficiency of the adjustment.

[0021] In the quantum bit coupling method provided in this disclosure, when it is determined that the initial coupling strength between quantum bits meets the preset long-range coupling condition, the quantum bits are coupled through the first coupler of the quantum bit coupler, which can improve the coupling strength between quantum bits, thereby enabling the quantum bits to work under the condition of higher coupling strength.

[0022] The quantum bit coupling method provided in this disclosure can also determine whether to adjust the first coupler based on the long-range coupling strength between the first and second quantum bits after the first coupler is coupled to the second coupler, thereby adjusting the first coupler in real time to improve the long-range coupling strength between the first and second quantum bits and achieve better operating efficiency between quantum bits that are far apart.

[0023] It should be understood that the description in this section is not intended to identify key or essential features of the embodiments of this disclosure, nor is it intended to limit the scope of this disclosure. Other features of this disclosure will become readily apparent from the following description. Attached Figure Description

[0024] The accompanying drawings are provided to better understand this solution and do not constitute a limitation of this disclosure. Wherein:

[0025] Figure 1 A first structural diagram of the coupling structure of a quantum bit provided in an embodiment of this disclosure;

[0026] Figure 2 A second structural diagram of the coupling structure of a quantum bit provided in an embodiment of this disclosure;

[0027] Figure 3 A third structural diagram of the coupling structure of a quantum bit provided in an embodiment of this disclosure;

[0028] Figure 4 A fourth structural diagram of the coupling structure of a quantum bit provided in an embodiment of this disclosure;

[0029] Figure 5 The fifth structural diagram of the coupling structure of the quantum bit provided in the embodiments of this disclosure;

[0030] Figure 6 A schematic diagram of a parallel-plate capacitor in the coupling structure of a quantum bit provided in an embodiment of this disclosure;

[0031] Figure 7 The sixth structural diagram of the coupling structure of the quantum bit provided in the embodiments of this disclosure;

[0032] Figure 8 A flowchart illustrating the quantum bit coupling method provided in this embodiment of the disclosure;

[0033] Figure 9 This is a block diagram of an electronic device that implements the quantum bit coupling method of the embodiments of this disclosure. Detailed Implementation

[0034] The exemplary embodiments of this disclosure are described below with reference to the accompanying drawings, including various details of the embodiments to aid understanding, and should be considered merely exemplary. Therefore, those skilled in the art will recognize that various changes and modifications can be made to the embodiments described herein without departing from the scope and spirit of this disclosure. Similarly, for clarity and brevity, descriptions of well-known functions and mechanisms are omitted in the following description.

[0035] Existing technologies divide multiple qubits into multiple clusters and connect the clusters through a bus to achieve long-range coupling between qubits that are spatially far apart. However, existing technologies have problems such as high requirements for the spatial arrangement of qubits, poor scalability, and high complexity.

[0036] In some embodiments of this disclosure, a coupling structure for qubits in a quantum device includes multiple qubits and a qubit coupler; wherein the multiple qubits are arranged in a specific manner, and the qubit coupler is capable of bending within the quantum device according to the specific arrangement of the multiple qubits.

[0037] The coupling structure disclosed herein includes a qubit coupler that can be bent according to a specific arrangement of multiple qubits, enabling the coupling structure to perform long-range coupling of qubits that are spatially distant in a quantum device through the qubit coupler. The long-range coupling refers to long-distance coupling between qubits. By performing long-range coupling between qubits through the qubit coupler, the direct interaction between coupled qubits can be reduced, thereby reducing crosstalk between qubits during coupling, so as to achieve high-fidelity quantum gate operation between long-distance qubits.

[0038] Figure 1 This is a first structural diagram of the coupling structure of a quantum bit provided in an embodiment of this disclosure. (See diagram below.) Figure 1 As shown, the present disclosure discloses a coupling structure of qubits in a quantum device, including multiple qubits and a qubit coupler; wherein the multiple qubits are arranged in a specific manner; the qubit coupler is configured to couple with the qubits, wherein the qubit coupler is capable of bending in the quantum device according to the specific arrangement of the multiple qubits.

[0039] The coupling structure includes a qubit coupler that can be bent according to a specific arrangement of multiple qubits, enabling long-range coupling of qubits that are spatially distant in a quantum device. Long-range coupling refers to long-distance coupling between qubits. By using the qubit coupler to achieve long-range coupling between qubits, the direct interaction between coupled qubits can be reduced, thereby reducing crosstalk between qubits during coupling and enabling high-fidelity quantum gate operations between long-distance qubits.

[0040] In some embodiments of this disclosure, the quantum device may be a quantum chip, a quantum computer, a quantum sensor, a quantum communication device, etc.; this embodiment does not limit the type of quantum device.

[0041] In some embodiments of this disclosure, the qubit can be a superconducting qubit, which is a type of qubit implementation. Superconducting qubits can utilize the quantum mechanical properties of superconducting materials to construct and manipulate quantum information.

[0042] In some embodiments of this disclosure, a plurality of qubits may include 8 qubits, 12 qubits, 16 qubits, 20 qubits, 100 qubits, 200 qubits, etc.; this disclosure does not limit the number of qubits, and the plurality of qubits may be arranged in a specific manner.

[0043] In some embodiments of this disclosure, multiple qubits are arranged in a specific configuration in a quantum device. This specific configuration may be periodic, with the qubits exhibiting a regular repetitive arrangement. Specifically, the specific configuration may be a square lattice configuration or a hexagonal lattice configuration. This disclosure does not limit the arrangement of qubits, which is beneficial for reducing the spatial arrangement requirements of qubits when there is long-range coupling between them.

[0044] In some embodiments of this disclosure, such as Figure 1 As shown, the specific arrangement of multiple qubits is a square lattice arrangement. The quantum device includes 16 qubits, which can be arranged in a 4×4 two-dimensional array. Specifically, the two-dimensional array includes 4 rows of qubits, with each row including 4 qubits.

[0045] In some embodiments of this disclosure, when coupling qubits using a quantum coupler, two qubits can be coupled using a quantum coupler, or one qubit can be coupled to a group of qubits using a quantum coupler. For example, as Figure 1 As shown, the quantum coupler can couple the first qubit of the first row to the first qubit of the fourth row, or it can couple all the qubits of the first row (e.g., ...). Figure 1 The dashed box surrounding the first row of qubits) and the first qubit in the fourth row (as shown in the image) Figure 1 Coupled with the dashed box surrounding the first qubit in the fourth row.

[0046] In some embodiments of this disclosure, the qubit coupler includes a first coupler and a second coupler. The first coupler is configured to couple non-adjacent qubits, and the second coupler is configured to couple adjacent qubits.

[0047] Since the first coupler is configured to couple non-adjacent qubits, the first coupler can be configured to couple with each qubit in the quantum device, thereby achieving long-range coupling between qubits through the first coupler.

[0048] In some embodiments of this disclosure, a first coupler is used to couple non-adjacent qubits to each qubit in the quantum device, wherein the non-adjacent qubits are qubits that are spatially far apart; a parallel plate capacitor located between the first coupler and the qubits can couple the first coupler to the qubits, or other couplers can be used, and this disclosure does not limit the use of such couplers.

[0049] In some embodiments of this disclosure, the first coupler may be a coplanar waveguide (CPW). A coplanar waveguide can be bent within a quantum device according to a specific arrangement of multiple qubits, coupling each qubit of the quantum device to the coplanar waveguide, thus coupling all qubits of the quantum device to the coplanar waveguide, thereby enabling long-range coupling of qubits that are spatially distant within the quantum device. Besides coplanar waveguides, the first coupler may also be other waveguides, photonic buses, etc., and this disclosure does not limit its application to these applications.

[0050] Specifically, in the coupling structure of the qubit disclosed herein, the coupling strength between the qubit and the first coupler can be determined using the following formula 1:

[0051]

[0052] In formula 1 above: g i ω represents the coupling strength between the i-th qubit and the first coupler; q ω is the frequency of the i-th qubit; r C is the frequency of the first coupler; i C is the capacitance of the i-th qubit; r C is the capacitance of the first coupler; ir Let be the coupling capacitance between the first coupler and the i-th qubit.

[0053] In this disclosure, the coupling strength between the first coupler and the quantum bit can be determined based on coupling parameters such as the frequency of the first coupler, the capacitance of the first coupler, and the coupling capacitance between the first coupler and the quantum bit.

[0054] This disclosure allows for adjusting the coupling capacitance between the first coupler and the qubit, for example, by adjusting the length of the first coupler and the distance between the first coupler and the qubit, thereby adjusting the coupling strength between the qubit and the first coupler. For instance, by adjusting the length and shape of the curved structure of the first coupler, the length of the first coupler and the distance between the first coupler and the qubit can be adjusted, thereby adjusting the coupling strength between the qubit and the first coupler.

[0055] This disclosure can also adjust the frequency of the first coupler, for example, by setting two Josephson junctions in parallel at one or both ends of the first coupler. The two Josephson junctions in parallel can adjust the frequency of the first coupler to adjust the coupling strength between the qubit and the first coupler.

[0056] The present disclosure can also adjust the capacitance of the first coupler, for example, by changing the length of the first coupler to adjust the coupling strength between the qubit and the first coupler, wherein the longer the length of the first coupler, the larger the capacitance of the first coupler, for example by adjusting the length and shape of the curved structure of the first coupler to adjust the length of the first coupler, thereby adjusting the coupling strength between the qubit and the first coupler.

[0057] In this disclosure, the coupling strength between the qubit and the first coupler is configured to determine the strength of the interaction between the qubit and the first coupler. The coupling strength affects the operating efficiency of the qubit, the time of quantum gate operation, and the transmission of quantum information.

[0058] In some embodiments of this disclosure, a second coupler coupling adjacent qubits is located between two adjacent qubits. This second coupler can be a capacitive coupler formed by two adjacent qubits; specifically, the second coupler couples the two adjacent qubits via capacitive coupling. This disclosure does not limit the number of second couplers in the qubit coupler, such as... Figure 1 As shown, the portion enclosed within the dotted-dash box is the second coupler between two adjacent qubits.

[0059] In some embodiments of this disclosure, the coupling structure of the qubit further includes a parallel plate capacitor disposed between the qubit and the first coupler, the parallel plate capacitor being formed by the qubit and the first coupler and configured to couple the qubit to the first coupler.

[0060] This disclosure allows a portion of the qubit and a portion of the first coupler to be treated as separate metal plates, which then serve as the two plates of a capacitor, thereby forming a parallel-plate capacitor between the qubit and the first coupler. Figure 6 As shown in the diagram, the portion within the dashed box represents a parallel-plate capacitor.

[0061] This disclosure enables coupling between a qubit and a first coupler using a parallel-plate capacitor. By adjusting the distance between the two metal plates of the parallel-plate capacitor or the length of the two metal plates, the coupling capacitance between the qubit and the first coupler can be changed, thereby adjusting the coupling strength between the qubit and the first coupler.

[0062] Specifically, this disclosure can adjust the curved structure shape of the first coupler to change the distance between the qubit and the first coupler, thereby adjusting the distance between the two metal plates in the parallel plate capacitor; this disclosure can also adjust the length of the curved structure of the first coupler to lengthen or shorten the length of the first coupler, thereby adjusting the length of the parallel plate capacitor.

[0063] In this disclosure, by adjusting the length and shape of the curved structure of the first coupler, the length of the first coupler and the distance between the first coupler and the qubit are adjusted, thereby adjusting the coupling strength between the qubit and the first coupler. When the number of qubits in the quantum device increases and multiple qubits present different specific arrangements, the curved structure of the first coupler can also enable long-range coupling of qubits that are spatially far apart, thereby forming a quantum device with a large number of qubits. This is beneficial to improving the scalability of the quantum device. Moreover, the long-range coupling between qubits in the quantum device through the curved structure of the first coupler can improve the flexibility of qubits when performing long-range coupling.

[0064] It is understood that when the first coupler in this disclosure is bent in a quantum device according to a specific arrangement of multiple qubits, the bending structure of the first coupler can be of various shapes, as long as it can ensure that each qubit in the quantum device is coupled to the first coupler. This disclosure does not impose any restrictions on this.

[0065] Figure 1 The bending structure of the first coupler is shown. The bending structure of the first coupler may include a return bend and a half-bend, such as... Figure 1 The portions enclosed by solid lines are the bends and half-bends. Specifically, a bend is provided on the right side between the first and second rows of qubits, and on the right side between the third and fourth rows of qubits; a half-bend is provided on the left side of the second and third rows of qubits. This disclosure achieves the bending of the first coupler according to the specific arrangement of the qubits by providing two bends and two half-bends, thus coupling the first coupler with all the qubits in the quantum device.

[0066] This disclosure can also employ other curved structures to couple the first coupler to all the qubits; specific curved structures can be further referenced. Figure 2 and Figure 3 , Figure 2 and Figure 3 The arrangement of multiple qubits in a medium and Figure 1 The multiple qubits in the array are arranged in the same way, all using a square lattice; among them, Figure 1 , Figure 2 and Figure 3 The black curved line in the middle represents the first coupler.

[0067] In some embodiments of this disclosure, the number or position of the bends and semi-bends can be set according to the specific pattern of the bending structure of the first coupler. For example, refer to... Figure 2 A half-bend is provided on the left side between the first and second rows of qubits, and a back-bend is provided on the right side between the first and second rows of qubits. Similarly, a half-bend is provided on the left side between the third and fourth rows of qubits, and a back-bend is provided on the right side between the third and fourth rows of qubits. This disclosure achieves the bending of the first coupler according to the specific arrangement of the qubits by providing two back-bends and two half-bends, thus enabling the first coupler in the quantum device to couple with all the qubits.

[0068] In some embodiments of this disclosure, the curved structure of the first coupler may also consist of only a half-bend. (See reference...) Figure 3 A half-bend is provided on the right side between the first row of qubits and the second row of qubits; a half-bend is provided on each of the left and right sides between the second row of qubits and the third row of qubits; a half-bend is provided on each of the left and right sides between the third row of qubits and the fourth row of qubits; and a half-bend is provided on the right side below the fourth row of qubits. By providing multiple half-bends, this disclosure enables the first coupler to bend according to the specific arrangement of the qubits, so that the first coupler in the quantum device is coupled with all the qubits.

[0069] Therefore, the bending structure of the first coupler in this disclosure includes at least a half-bend and may further include a back bend. Through the bending structure of the first coupler, the first coupler can be bent in the quantum device, thereby coupling the first coupler with all the qubits in the quantum device.

[0070] In this disclosure, as the number of qubits increases and multiple qubits exhibit different specific arrangements, the bending structure of the first coupler can change its length and shape according to the number of qubits and specific arrangements. Thus, even when the number of qubits in the quantum device increases and multiple qubits exhibit different specific arrangements, the first coupler can also couple qubits that are spatially distant over long distances, thereby forming a quantum device with a large number of qubits. This is beneficial to improving the scalability of the quantum device. Furthermore, the long-distance coupling between qubits through the bending structure of the first coupler can enhance the flexibility of qubits when performing long-distance coupling.

[0071] Specifically, in the coupling structure of the qubits disclosed herein, the coupling strength between two qubits coupled through the first coupler can be determined using the following formula 2:

[0072]

[0073] In formula 2 above: g ij g represents the coupling strength between the i-th qubit and the j-th qubit. i g represents the coupling strength between the i-th qubit and the first coupler; j Let Δ be the coupling strength between the j-th qubit and the first coupler; i Δ represents the difference between the frequency of the i-th qubit and the frequency of the first coupler; j This represents the difference between the frequency of the j-th qubit and the frequency of the first coupler.

[0074] From Formula 2 above, it can be seen that this disclosure can adjust the coupling strength between qubits by adjusting the coupling strength between the qubit and the first coupler, or by adjusting the difference between the frequency of the qubit and the frequency of the first coupler, i.e., changing Δ in Formula 2 above. i With Δ j This is to adjust the coupling strength between qubits.

[0075] Specifically, this disclosure adjusts the frequency difference Δ between the first coupler and the quantum bit. i Or Δ j At that time, the frequency of the first coupler is adjusted to match the frequency of the i-th or j-th qubit to reduce Δ. i Or Δ j This increases the coupling strength between the i-th qubit and the j-th qubit.

[0076] This disclosure allows for adjustment of the coupling strength between two qubits coupled by the first coupler by adjusting the frequency of the first coupler, thereby simplifying the process of adjusting the coupling strength between qubits and improving the efficiency of adjusting the coupling strength between qubits.

[0077] Figure 4 This is a fourth structural diagram of the coupling structure of a quantum bit provided in an embodiment of this disclosure. (See diagram below.) Figure 4 As shown, the coupling structure of the qubit disclosed herein, in addition to including multiple qubits and a first coupler, may also include two Josephson junctions connected in parallel at one or both ends of the first coupler. Figure 4 The following example illustrates the use of two Josephson junctions connected in parallel at both ends of the first coupler.

[0078] In some embodiments of this disclosure, two Josephson junctions connected in parallel at either end of the first coupler form a superconducting quantum interference device (SQUID). In this disclosure, two Josephson junctions are connected in parallel at both ends of the first coupler to form two superconducting quantum interference devices.

[0079] In some embodiments of this disclosure, the frequency of the first coupler is adjusted by regulating the mutual inductance of a superconducting quantum interference device disposed at either end of the first coupler, thereby adjusting the coupling strength between two qubits coupled through the first coupler.

[0080] In other words, by setting superconducting quantum interference devices at both ends of the first coupler, the superconducting quantum interference devices can change the frequency of the first coupler. This allows the coupling strength between qubits to be adjusted by changing the frequency of the first coupler while keeping the state of the qubits unchanged. This simplifies the process of adjusting the coupling strength between qubits and improves the flexibility and efficiency of the adjustment.

[0081] Figure 5 This is the fifth structural diagram of the coupling structure of a quantum bit provided in an embodiment of this disclosure. (See diagram below.) Figure 5 As shown, Figure 5 The diagram illustrates multiple qubits arranged in a hexagonal lattice in a quantum device, and a first coupler coupled to all the qubits arranged in the hexagonal lattice. Figure 5 In this system, the coupling structure of the qubits includes 12 qubits, a first coupler, and two Josephson junctions connected in parallel at both ends of the first coupler.

[0082] Figure 6 This is a schematic diagram of a parallel-plate capacitor in the coupling structure of a quantum bit provided in an embodiment of this disclosure. Figure 6 As shown, the parallel-plate capacitor is formed by a first coupler and a quantum bit, wherein the first coupler can be a coplanar waveguide. Figure 6 The portion enclosed by the dashed box is the parallel plate capacitor between the first coupler and the qubit.

[0083] from Figure 6As can be seen from the above, this disclosure can reduce the distance between the qubit and the coplanar waveguide by adjusting the curved structure shape of the first coupler, thereby reducing the distance between the two plates in the parallel-plate capacitor and increasing the coupling capacitance between the qubit and the coplanar waveguide. This disclosure can also shorten the length of the coplanar waveguide by adjusting the length of the curved structure of the first coupler, thereby reducing the length of the parallel-plate capacitor between the qubit and the coplanar waveguide and increasing the coupling capacitance between the qubit and the coplanar waveguide.

[0084] When the coupling capacitance between the qubit and the first coupler increases, according to Formula 1, the coupling strength between the qubit and the first coupler increases; further according to Formula 2, when the coupling strength between the qubit and the first coupler increases, the coupling strength between the two qubits coupled through the first coupler also increases, thereby adjusting the coupling strength between the qubits.

[0085] Figure 7 The sixth structural diagram of the coupling structure of the quantum bit provided in the embodiments of this disclosure is shown. Figure 7 As shown, this disclosure illustrates a coupling structure comprising 32 qubits and two first couplers, wherein the 32 qubits are arranged in a 4×8 two-dimensional array, specifically, the two-dimensional array comprising 4 rows of qubits, each row comprising 8 qubits.

[0086] and Figures 1-3 Compared to the coupling structure shown in the diagram, the number of qubits and the number of first couplers in the coupling structure of this disclosure have changed. Specifically, as the number of qubits changes, the number of first couplers in this disclosure also changes accordingly.

[0087] In other words, this disclosure allows for the corresponding increase in the number of first couplers as the number of qubits increases, thereby forming a quantum device with a large number of qubits. This is beneficial for improving the scalability of the quantum device. Furthermore, the quantum device uses multiple first couplers to perform long-range coupling between qubits, which can enhance the flexibility of qubits when performing long-range coupling.

[0088] Figure 8 A flowchart illustrating a quantum bit coupling method provided in an embodiment of this disclosure. Figure 8 As shown, the quantum bit coupling method disclosed herein includes the following steps:

[0089] S801, Obtain the initial coupling strength between the first qubit and the second qubit;

[0090] S802, when the initial coupling strength meets the preset long-range coupling condition, the first quantum bit and the second quantum bit are coupled through the first coupler in the quantum bit coupler.

[0091] The quantum bit coupling method disclosed herein performs long-range coupling based on the quantum bit coupling structure of the above embodiments. Quantum bits that are spatially far apart are coupled through a first coupler. When it is determined that the initial coupling strength between quantum bits meets the preset long-range coupling conditions, the quantum bits are coupled through the first coupler, which can improve the coupling strength between quantum bits, thereby enabling the quantum bits to work under the condition of higher coupling strength.

[0092] In some embodiments of this disclosure, the first qubit and the second qubit are two qubits disposed in a quantum device, and the two qubits are coupled to perform quantum gate operations and information transmission, etc.

[0093] The initial coupling strength obtained in step S801 of this disclosure can be the coupling strength when the first quantum bit and the second quantum bit are coupled through the second coupler in the quantum coupler.

[0094] In some embodiments of this disclosure, the initial coupling strength is obtained by calculation. Specifically, the initial coupling strength between the first qubit and the second qubit is determined based on the distance between the first qubit and the second qubit when they are coupled through the second coupler.

[0095] In some embodiments of this disclosure, the coupling strength is configured to determine the strength of the interaction between qubits, which affects the operating efficiency of qubits, the time of quantum gate operations, and the transmission of quantum information.

[0096] In step S802 of this disclosure, when determining whether the initial coupling strength meets the preset long-range coupling condition, the initial coupling strength can be determined to meet the preset long-range coupling condition if it is less than a first preset strength threshold. The first preset strength threshold can be a small value, such as 1 MHz or 0.5 MHz. In this embodiment, if the initial coupling strength is determined to be small, the preset long-range coupling condition is determined to be met, thereby enabling long-range coupling between the first and second qubits.

[0097] In some embodiments of this disclosure, two adjacent qubits can be either closely adjacent or far adjacent. For closely adjacent qubits, they can be coupled using a second coupler. For far adjacent qubits, due to the greater distance between them, the initial coupling strength when coupled using a second coupler is relatively low, thus requiring long-range coupling using a first coupler.

[0098] For two non-adjacent qubits, they cannot be coupled through a second coupler. The initial coupling strength between the two qubits is 0 or a small value. The initial coupling strength satisfies the preset long-range coupling condition, thereby enabling long-range coupling of the two qubits through the first coupler.

[0099] It is understood that when performing step S802, if it is determined that the initial coupling strength does not meet the preset long-range coupling condition, it indicates that the coupling strength between the first quantum bit and the second quantum bit through the second coupler of the quantum coupler is high. Therefore, there is no need to couple through the first coupler, and the second coupler of the quantum coupler is used for coupling.

[0100] In some embodiments of this disclosure, after performing step S802, which couples the first qubit and the second qubit through the first coupler, the disclosure may further include: obtaining the long-range coupling strength between the first qubit and the second qubit, for example, using formulas 1 and 2 in the above embodiments, wherein the long-range coupling strength is the coupling strength when the first qubit and the second qubit are coupled through the first coupler. If the long-range coupling strength meets preset adjustment conditions, the first coupler is adjusted to improve the long-range coupling strength when the qubits are coupled.

[0101] In some embodiments of this disclosure, when determining whether the long-range coupling strength meets the preset adjustment conditions in step S802, the disclosure can determine that the preset adjustment conditions are met if the long-range coupling strength is less than a second preset strength threshold. The second preset strength threshold is preset, for example, 10 MHz, 20 MHz, etc., and can be the coupling strength required for quantum gate operations to achieve better operational efficiency between qubits. The second preset strength threshold can be greater than or equal to the first preset strength threshold.

[0102] When adjusting the first coupler in step S802, this disclosure allows for the adjustment of the coupling parameters of the first coupler, such as adjusting at least one of the frequency of the first coupler, the capacitance of the first coupler, and the coupling capacitance between the first coupler and the quantum bit.

[0103] In step S802, the frequency of the first coupler can be adjusted by a superconducting quantum interference device located at either end of the first coupler, for example, by increasing the frequency of the first coupler or making the frequency of the first coupler consistent with the frequency of the quantum bit.

[0104] In performing step S802, this disclosure can also adjust the coupling capacitance between the qubit and the first coupler by using a parallel plate capacitor disposed between the qubit and the first coupler, for example by reducing the distance of the parallel plate capacitor or reducing the length of the parallel plate capacitor.

[0105] In performing step S802, this disclosure may also change the length of the first coupler to adjust the capacitance of the first coupler, for example, by increasing the length of the first coupler to increase the capacitance of the first coupler.

[0106] In performing step S802, this disclosure can also simultaneously adjust the superconducting quantum interference device and the parallel plate capacitor, thereby adjusting the coupling parameters of the first coupler.

[0107] In performing step S802, this disclosure can determine that the adjustment is complete when the long-range coupling strength between the first quantum bit and the second quantum bit reaches a second preset strength threshold. In this disclosure, the second preset strength threshold can be 10 MHz, 20 MHz, etc.

[0108] This disclosure allows for real-time adjustment of the coupling parameters of the first coupler to adjust the long-range coupling strength between qubits coupled through the first coupler, thereby improving the long-range coupling strength between qubits.

[0109] This disclosure also provides an electronic device. For example... Figure 9 The diagram shown is a block diagram of an electronic device for a quantum bit coupling method according to an embodiment of the present disclosure. The electronic device is intended to represent various forms of devices, such as quantum computers, laptop computers, desktop computers, workbenches, personal digital assistants, servers, blade servers, mainframe computers, and other suitable computers. The electronic device may also represent various forms of mobile devices, such as personal digital processors, cellular phones, smartphones, wearable devices, and other similar computing devices. The components shown herein, their connections and relationships, and their functions are merely illustrative and are not intended to limit the implementation of the present disclosure described and / or claimed herein.

[0110] like Figure 9As shown, the electronic device 900 includes a computing unit 901, which can perform various appropriate actions and processes according to a computer program stored in a read-only memory (ROM) 902 or a computer program loaded from a storage unit 908 into a random access memory (RAM) 903. The RAM 903 may also store various programs and data required for the operation of the device 900. The computing unit 901, ROM 902, and RAM 903 are interconnected via a bus 904. An input / output (I / O) interface 905 is also connected to the bus 904.

[0111] Components connected to the I / O interface 905 in the electronic device 900 include: an input unit 906, such as a keyboard or mouse; an output unit 907, such as various types of displays or speakers; a storage unit 908, such as a disk or optical disk; and a communication unit 909, such as a network interface card (NIC), a modem, or a wireless transceiver. The communication unit 909 allows the electronic device 900 to exchange information / data with other devices through computer networks such as the Internet and / or various telecommunications networks.

[0112] The computing unit 901 can be a variety of general-purpose and / or special-purpose processing components with processing and computing capabilities. Some examples of the computing unit 901 include, but are not limited to, a central processing unit (CPU), a graphics processing unit (GPU), various special-purpose artificial intelligence (AI) computing chips, various computing units running machine learning model algorithms, a digital signal processor (DSP), and any suitable processor, controller, microcontroller, etc. The computing unit 901 performs the various methods and processes described above, such as the qubit coupling method. For example, in some embodiments, the qubit coupling method can be implemented as a computer software program tangibly contained in a machine-readable medium, such as storage unit 908.

[0113] In some embodiments, part or all of the computer program may be loaded and / or installed on the electronic device 900 via ROM 902 and / or communication unit 909. When the computer program is loaded into RAM 903 and executed by computing unit 901, one or more steps of the qubit coupling method described above may be performed. Alternatively, in other embodiments, computing unit 901 may be configured to perform the qubit coupling method by any other suitable means (e.g., by means of firmware).

[0114] Various implementations of the systems and techniques described herein can be implemented in digital electronic circuit systems, integrated circuit systems, field-programmable gate arrays (FPGAs), application-specific integrated circuits (ASICs), application-specific standard products (ASSPs), systems-on-a-chip (SoCs), complex programmable logic devices (CPLDs), computer hardware, firmware, software, and / or combinations thereof. These various implementations may include implementations in one or more computer programs that can be executed and / or interpreted on a programmable system including at least one programmable processor, which may be a dedicated or general-purpose programmable processor, capable of receiving data and instructions from a storage system, at least one input device, and at least one output device, and transferring data and instructions to the storage system, the at least one input device, and the at least one output device.

[0115] The program code used to implement the methods of this disclosure may be written in any combination of one or more programming languages. This program code may be provided to a processor or controller of a general-purpose computer, a special-purpose computer, or other coupler between programmable qubits, such that when executed by the processor or controller, the functions / operations specified in the flowcharts and / or block diagrams are implemented. The program code may be executed entirely on a machine, partially on a machine, as a standalone software package partially on a machine and partially on a remote machine, or entirely on a remote machine or server.

[0116] In the context of this disclosure, a machine-readable medium can be a tangible medium that may contain or store a program for use by or in conjunction with an instruction execution system, apparatus, or device. A machine-readable medium can be a machine-readable signal medium or a machine-readable storage medium. A machine-readable medium can be, but is not limited to, electronic, magnetic, optical, electromagnetic, infrared, or semiconductor systems, apparatus, or devices, or any suitable combination of the foregoing. More specific examples of machine-readable storage media include electrical connections based on one or more wires, portable computer disks, hard disks, random access memory (RAM), read-only memory (ROM), erasable programmable read-only memory (EPROM or flash memory), optical fiber, portable compact disk read-only memory (CD-ROM), optical storage devices, magnetic storage devices, or any suitable combination of the foregoing.

[0117] To provide interaction with a user, the systems and techniques described herein can be implemented on a computer having: a display device for showing information to the user (e.g., a CRT (cathode ray tube) or LCD (liquid crystal display) monitor); and a keyboard and pointing device (e.g., a mouse or trackball) through which the user provides input to the computer. Other types of devices can also be used to provide interaction with the user; for example, feedback provided to the user can be any form of sensory feedback (e.g., visual feedback, auditory feedback, or tactile feedback); and input from the user can be received in any form (including sound input, voice input, or tactile input).

[0118] The systems and technologies described herein can be implemented in computing systems that include backend components (e.g., as a data server), or computing systems that include middleware components (e.g., an application server), or computing systems that include frontend components (e.g., a user computer with a graphical user interface or web browser through which a user can interact with implementations of the systems and technologies described herein), or any combination of such backend, middleware, or frontend components. The components of the system can be interconnected via digital data communication (e.g., a communication network) of any form or medium. Examples of communication networks include local area networks (LANs), wide area networks (WANs), and the Internet.

[0119] Computer systems can include clients and servers. Clients and servers are generally geographically separated and typically interact via communication networks. The client-server relationship is created by computer programs running on the respective computers and having a client-server relationship with each other. A server can be a cloud server, also known as a cloud computing server or cloud host, a hosting product within the cloud computing service system that addresses the shortcomings of traditional physical hosts and VPS (Virtual Private Server, or simply "VPS") services, such as high management difficulty and weak business scalability. Servers can also be servers for distributed systems or servers incorporating blockchain technology.

[0120] This disclosure also provides a computer storage medium storing computer instructions, which, when executed by a processor, implement the quantum bit coupling method provided in the above embodiments.

[0121] It should be understood that the various forms of processes shown above can be used to rearrange, add, or delete steps. For example, the steps described in this disclosure can be executed in parallel, sequentially, or in different orders, as long as the desired result of the technical solution disclosed in this disclosure can be achieved, and this is not limited herein.

[0122] The specific embodiments described above do not constitute a limitation on the scope of protection of this disclosure. Those skilled in the art should understand that various modifications, combinations, sub-combinations, and substitutions can be made according to design requirements and other factors. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of this disclosure should be included within the scope of protection of this disclosure.

Claims

1. A coupling structure of qubits, disposed in a quantum device, comprising: a plurality of qubits arranged in a specific arrangement; a qubit coupler configured to couple with the qubits, wherein the qubit coupler is capable of being bent in the quantum device according to the specific arrangement of the plurality of qubits. The qubit coupler comprises a first coupler and a second coupler; wherein the first coupler is configured to couple non-adjacent qubits, and the second coupler is configured to couple adjacent qubits.

2. The coupling structure of claim 1, wherein, 3.The coupling structure of claim 2, further comprising a parallel-plate capacitor, The parallel-plate capacitor is disposed between the qubit and the first coupler, and is configured to couple the qubit and the first coupler. The coupling strength between the first coupler and the qubit is determined based on a coupling parameter, the coupling parameter comprising at least one of a frequency of the first coupler, a capacitance of the first coupler, and a coupling capacitance between the first coupler and the qubit. 5.The coupling structure of claim 2, further comprising two Josephson junctions in parallel, 4. The coupling structure of claim 2, wherein, The two Josephson junctions in parallel are disposed at one end or both ends of the first coupler, and are configured to adjust the frequency of the first coupler. The coupling capacitance between the first coupler and the qubit is determined based on a length of the first coupler or a distance between the first coupler and the qubit. 7.A method of coupling qubits, comprising: obtaining an initial coupling strength between a first qubit and a second qubit; 6. The coupling structure of claim 4, wherein, in a case where the initial coupling strength satisfies a preset long-range coupling condition, performing long-range coupling between the first qubit and the second qubit by a first coupler in a qubit coupler; wherein the qubit coupler is the qubit coupler of any one of the coupling structures of claims 1-6. The initial coupling strength satisfying the preset long-range coupling condition comprises: in a case where the initial coupling strength is less than a first preset strength threshold, determining that the initial coupling strength satisfies the preset long-range coupling condition, wherein the initial coupling strength is a coupling strength when a second coupler in the qubit coupler couples the first qubit and the second qubit. 9.The method of claim 7, further comprising, 8. The method of claim 7, wherein, after performing long-range coupling between the first qubit and the second qubit by the first coupler in the qubit coupler, obtaining a long-range coupling strength between the first qubit and the second qubit; in a case where the long-range coupling strength satisfies a preset adjustment condition, adjusting the first coupler to improve the long-range coupling strength. The long-range coupling strength satisfying the preset adjustment condition comprises: in a case where the long-range coupling strength is less than a second preset strength threshold, determining that the long-range coupling strength satisfies the preset adjustment condition. The adjusting the first coupler comprises:

10. The method of claim 9, wherein, ​ ​ 11. The method of claim 9, wherein, ​ adjusting a coupling parameter of the first coupler, the coupling parameter comprising at least one of a frequency of the first coupler, a capacitance of the first coupler, a coupling capacitance between the first coupler and the qubit. 12.An electronic device comprising: at least one processor; and a memory connected with the at least one processor in communication; wherein, the memory stores instructions executable by the at least one processor, the instructions being executed by the at least one processor to enable the at least one processor to perform the method of any one of claims 7-11.

13. A non-transitory computer storage medium having computer instructions stored therein, wherein, the computer instructions are configured to cause the computer to perform the method of any one of claims 7-11.

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