Superconducting quantum bit, chip and computer

Abstract

The utility model discloses a superconducting quantum bit, a chip and a computer, and belongs to the field of quantum computing. And the superconducting quantum bits are positioned through the first region, the second region and the third region which are adjacent in sequence. The superconducting quantum bit includes a bit capacitor, a Josephson junction circuit, and a connection circuit. Comprising a first capacitor plate and a second capacitor plate which are spaced apart is located in the first area; the Josephson junction circuit is located in the third region; the main body part of the connecting circuit is located in the second area, and the two ends of the connecting circuit extend to the first area and the third area respectively and are electrically connected with the Josephson junction circuit, the first capacitor plate and the second capacitor plate respectively and correspondingly. The superconducting quantum bit constructed through the structural form can be controlled more accurately and effectively, and therefore the accuracy and effectiveness of the result of executed quantum calculation based on the superconducting quantum bit can be improved.

Description

Technical Field

[0001] This application belongs to the field of quantum computing. In particular, this application relates to a superconducting qubit, a chip, and a computer. Background Art

[0002] The frequency-tunable superconducting qubit has two control channels. One is the high-frequency control channel, which controls the xy rotation of the superconducting qubit through capacitive coupling and can be specifically implemented as the xy control line. The other is the low-frequency control channel, which controls the Z-axis rotation of the superconducting qubit through inductive coupling. The reasonable layout of the control lines has an important impact on the precise and effective control of the qubit. Summary of the Utility Model

[0003] Examples of this application provide a superconducting qubit, a chip, and a computer. This solution can be used to improve the control accuracy and effectiveness of qubits in a superconducting quantum chip and reduce the adverse effects of noise signals.

[0004] The solution of the example of this application is implemented through the following content.

[0005] In a first aspect, an example of this application discloses a superconducting qubit.

[0006] The superconducting qubit is defined with a qubit distribution region and includes a first region, a second region, and a third region that are adjacent to each other in sequence.

[0007] The superconducting qubit includes:

[0008] A qubit capacitor formed by a first capacitor plate and a second capacitor plate located in the first region and spaced apart from each other;

[0009] A Josephson junction circuit located in the third region; and

[0010] A connection circuit with the main body part located in the second region, the two ends of the connection circuit extending to the first region and the third region respectively, one end of the connection circuit being electrically connected to the Josephson junction circuit and the other end being electrically connected to the first capacitor plate and the second capacitor plate.

[0011] According to some examples of this application, the first capacitor plate and the second capacitor plate have the same area.

[0012] According to some examples of this application, the first capacitor plate and the second capacitor plate have the same shape.

[0013] According to some examples of this application, the Josephson junction circuit includes a superconducting quantum interference device circuit.

[0014] According to some examples of the present application, the connection circuit includes an independent first branch and a second branch. The first branch is integrally formed with the first capacitor plate, and the second branch is integrally formed with the second capacitor plate.

[0015] According to some examples of the present application, the Josephson junction circuit includes a superconducting quantum interference device (SQUID) circuit;

[0016] The SQUID circuit includes:

[0017] A transverse circuit connected to the first branch, having a first end and a second end distributed at both transverse ends;

[0018] A first longitudinal circuit and a second longitudinal circuit respectively connected to the second branch;

[0019] The first longitudinal circuit intersects the transverse circuit at the first end, and a first Josephson junction is formed at the intersection; and

[0020] The second longitudinal circuit intersects the transverse circuit at the second end, and a second Josephson junction is formed at the intersection.

[0021] In a second aspect, an example of the present application discloses a superconducting quantum chip including the aforementioned superconducting quantum bit.

[0022] In a third aspect, an example of the present application discloses a superconducting quantum chip, including:

[0023] A substrate, on the surface of which a superconducting metal film providing a ground plane is provided, and the superconducting metal film is formed with through holes exposing the surface; and

[0024] The aforementioned superconducting quantum bit, and the bit distribution area is located in the area defined by the through holes, such that the superconducting quantum bit is located within the through holes.

[0025] According to some examples of the present application, the Josephson junction circuit is disposed adjacent to the ground plane.

[0026] In a fourth aspect, an example of the present application discloses a quantum computer including the above-mentioned superconducting quantum bit and superconducting quantum chip.

[0027] In an example of the present disclosure, the superconducting quantum bit has a double-island structure, that is, the bit capacitor has two capacitor plates spaced apart from each other. Moreover, the nonlinear inductor part (including the circuit of the Josephson junction, that is, the Josephson junction circuit) constituting the superconducting quantum bit is far from the bit capacitor.

[0028] Since the Josephson junction circuit is far from the capacitor plate, therefore, when applying this superconducting quantum to construct superconducting quantum devices, equipment, etc. (such as superconducting quantum chips), the control structure of the bit - for example, for a bit with adjustable frequency - its frequency control circuit (which can be simply referred to as the Z line) can also be far from the bit capacitor.

[0029] On this basis, since the frequency control line is far from the bit capacitor, while ensuring that the mutual inductance between the frequency control line and the bit meets the frequency control requirements, the mutual capacitance between the frequency control line and the bit will be relatively small, reducing the noise signal introduced by the frequency control line, thereby ensuring the accuracy and effectiveness of the frequency control. Description of the Drawings

[0030] For a clearer illustration, the drawings required for the description will be briefly introduced below.

[0031] Figure 1 Schematic diagram of the structure of a qubit on a quantum chip in the related art;

[0032] Figure 2 Schematic diagram of the structure of the bit capacitor in a double-island bit in the present application;

[0033] Figure 3 Shows a structure based on Figure 2 Schematic diagram of the relative position of the capacitor plates in the bit capacitor shown and the Z control line;

[0034] Figure 4 Schematic diagram of the relative position of the capacitor plates in the bit capacitor in another double-island bit in the example of the present application and the Z control line;

[0035] Figure 5 Discloses the schematic diagram of the structure of the superconducting qubit in the example of the present application;

[0036] Figure 6 Shows a structure related to Figure 5 Schematic diagram of the relative position of the frequency control line that cooperates with the frequency of the superconducting qubit shown to achieve frequency control of the qubit;

[0037] Figure 7 Discloses the Figure 5 Schematic diagram of the structure of the Josephson junction in the Josephson junction circuit of the superconducting qubit shown in the example of the present application;

[0038] Figure 8 Is a structure based on Figure 7 Schematic diagram of the structure of the connection components provided in the Josephson junction circuit shown.

[0039] Description of the Reference Numerals:

[0040] 101 - First capacitor plate; 102 - Second capacitor plate;

[0041] 201 - First branch; 202 - Second branch;

[0042] 203 - Josephson junction circuit;

[0043] 301 - First longitudinal circuit; 302 - Second longitudinal circuit; 303 - Transverse circuit; 304 - Connection component. Detailed implementation mode

[0044] A quantum chip based on a superconducting quantum circuit includes superconducting circuit structures such as qubits and microwave resonators.

[0045] Among them, a qubit is a two-level system composed of a capacitor and a Josephson junction with nonlinear inductance characteristics. By designing different shapes, electrical parameter states such as capacitance and inductance with different objectives can be achieved.

[0046] The shape of a Transmon qubit (transmon qubit) is similar to a "+", and it consists of a cross-shaped capacitor and a superconducting quantum interference device (Superconducting Quantum Interference Device, abbreviated as squid) connected to the end of one branch of the capacitor.

[0047] Among them, the superconducting quantum interference device (squid) includes one or more Josephson junctions; a Josephson junction is a device including two electrodes and a thin insulating potential barrier layer separating the two electrodes, and the materials of the two electrodes can exhibit superconducting characteristics at their own critical temperatures or exhibit superconducting characteristics at temperatures below the critical temperature characteristics.

[0048] In the above qubit system, there are various circuit structures with different functions around the qubit. For example, a read resonator for reading the quantum state of the qubit, and a coupler for coupling and connecting between qubits.

[0049] In addition to the above read resonator and coupler, the circuit structure can also include a drive control signal line (xy-Control Line, also known as xy control line or pulse modulation signal line) for performing xy rotation operations on the qubit. When in use, by applying a drive voltage signal in the circuit, the qubit can be excited to transition; it is associated with the qubit through capacitive coupling.

[0050] Furthermore, the circuit structure can also include a circuit structure for performing Z rotation operations on the qubit, and it is completed by the control signal line near the superconducting quantum interference device (squid). It is called a flux modulation signal line (Z-Control Line, also known as z control line or frequency modulation signal line). The flux modulation signal line is arranged near the superconducting quantum interference device (squid), which excites current and is mutually inductively coupled with the superconducting quantum interference device (squid) through a magnetic field.

[0051] It should be noted that both the magnetic flux control signal line and the drive control line can be used to control qubits, but their control forms and purposes are essentially different.

[0052] Among them, the drive control signal line applies a pulse to the qubit in the form of an electric field, and this pulse causes the energy level of the qubit to transition. The signal transmitted by the magnetic flux control signal line will generate a magnetic field and apply it to the superconducting quantum interference device (SQUID) region. At the same time, the magnetic flux passing through the SQUID region can cause a change in the critical current of the SQUID. This change in the critical current leads to a change in the frequency of the tunable qubit, that is, the frequency of the qubit can be controlled by the signal transmitted by the magnetic flux control signal line.

[0053] Figure 1 It is a schematic diagram of the structure of qubits arranged on a quantum chip in the related art.

[0054] Combined with Figure 1 as shown, the structure of the qubit often adopts a single capacitor grounded to the ground, and a superconducting quantum interference device with one end grounded and the other end connected to the capacitor. And this capacitor is Figure 1 a cross-shaped capacitor plate in the example.

[0055] Referring to Figure 1 as shown, the cross-shaped capacitor plate C q (i.e., the qubit capacitor) is surrounded by a ground plane (GND), and there is a gap (usually an air gap, insulating) between the cross-shaped capacitor plate C q and the ground plane (GND).

[0056] One end of the superconducting quantum interference device is connected to the cross-shaped capacitor plate C q (the end of a capacitor arm, such as the first end mentioned later), and the other end is connected to the ground plane (GND).

[0057] Since the first end of the cross-shaped capacitor plate C q is usually used to connect the superconducting quantum interference device, the second end (collinear with the first end) is used to couple with the read resonator. And the other two ends of the cross-shaped capacitor plate C q are used to couple with adjacent qubits to achieve qubit expansion. A certain amount of space is usually reserved near the first end and the second end for arranging microwave transmission lines such as drive control signal lines and magnetic flux control signal lines. Similarly, a certain amount of space is usually reserved near the resonator for arranging the read signal transmission line that forms a coupling with the resonator.

[0058] When performing quantum computing, the flux control signal on the flux control signal line is used to first adjust the frequency of the qubit to the operating frequency (initial state preparation), and then a quantum state control signal is applied through the drive control signal line to perform quantum state control on the qubit in the initial state. Then, a resonator is used to read the quantum state of the controlled qubit.

[0059] Specifically, a read detection signal (for example, a microwave signal with a frequency of 4 GHz - 8 GHz) can be applied to the read signal transmission line coupled to the resonator, and then the read feedback signal (a signal in response to the read detection signal) output from the read signal transmission line is analyzed to determine the quantum state of the qubit. Structures such as the flux control signal line, the drive control signal line, and the read signal transmission line can all adopt microwave transmission line structures, which will not be elaborated here.

[0060] It should be noted that the quantum chip performs quantum computing as follows:

[0061] The waveform instructions and the like generated by compiling the quantum program in the quantum computing task are sent to the physical signal generation device. The physical signal generation device generates corresponding physical signals, which are sent to the quantum chip to operate the corresponding qubits. Then, a quantum state read signal is applied to the corresponding qubit, and the quantum state information of the qubit is determined according to the read feedback signal fed back by the qubit based on the quantum state read signal. Finally, the quantum computing result is analyzed.

[0062] To provide greater flexibility in wiring in the chip, in some improvement schemes, the Figure 1 shown bit structure is optimized. For example, in Figure 1 , the structure of the bit capacitor is a cross-shaped structure, and this bit is described as a single-island bit. Therefore, as a practice of the improvement scheme, the bit capacitor is adjusted from the Figure 1 single-island bit to the bit capacitor in the form of a double island in the double-island bit (refer to Figure 2 ). The main improvement points in the double-island bit are as follows: Figure 1 The bit capacitor in

[0063] However, in actual use, the applicant found that the double-bit in the above structural form has a problem that the control result deviates from the control target during the controlled process, and this deviation may be so large that normal quantum computing cannot be performed.

[0064] After analysis, the applicant found that the factor causing this problem is that in this form of double-island bit, the control line (especially the Z control line) will penetrate between the two capacitor plates. For example, in Figure 3That is, the Z control line is configured to be disposed between two capacitor plates, and one superconducting electrode of the Josephson junction is electrically connected to one of the two capacitor plates, while the other superconducting electrode of the Josephson junction is electrically connected to the other of the two capacitor plates near the Josephson junction.

[0065] In some attempts, it is possible to choose to configure the Josephson junction at the end of a capacitor plate; that is, one superconducting electrode of the Josephson junction is connected to the capacitor plate, and the other superconducting electrode is connected to the ground plane. Refer to Figure 4 However, in practice, there are still some of the above problems with this scheme.

[0066] In view of this, the applicant has proposed a new two-island qubit structure, thereby alleviating and improving the above problems to a considerable extent.

[0067] In the example of this application, the improvements of the proposed new two-island qubit mainly lie in the shape of the capacitor plates and the setting position of the Josephson junction relative to the capacitor plates.

[0068] For example, as Figure 5 shown, for the convenience of description, it is assumed that the superconducting qubit in this application is defined with a qubit distribution region, and the qubit distribution region includes a first region, a second region, and a third region that are adjacent in sequence. As Figure 5 shown, the first region, the second region, and the third region are distributed in sequence from left to right.

[0069] Based on the above-defined three regions, the superconducting qubit includes a qubit capacitor, a Josephson junction circuit 203, and a connection circuit.

[0070] The qubit capacitor is composed of a first capacitor plate 101 and a second capacitor plate 102. Moreover, the first capacitor plate 101 and the second capacitor plate 102 are located in the first region. At the same time, the first capacitor plate 101 and the second capacitor plate 102 are spaced apart from each other.

[0071] The Josephson junction circuit 203 is located in the third region.

[0072] The connection circuit with the main body part located in the second region, and both ends of the connection circuit extend to the first region and the third region respectively. At the same time, one end of the connection circuit is electrically connected to the Josephson junction circuit 203, and the other end is electrically connected to the first capacitor plate 101 and the second capacitor plate 102.

[0073] In the structure of the superconducting qubit described above, the region where the Josephson junction is located (the third region) is far from the region where the capacitor plates are located (the first region). Due to the large distance between the first region and the third region, the distance between the Josephson junction and the capacitor plates is relatively far. On this basis, when it is necessary to control the superconducting qubit (such as qubit frequency adjustment), a frequency control line can be set near the third region.

[0074] By setting the frequency control line in a region far from the capacitor plates of the qubit, that is, near the third region, the mutual capacitance between the control line and the capacitor plates is greatly reduced, thereby limiting the adverse effects of the frequency control line on the qubit. That is to say, one of the important improvements of the superconducting qubit involved in this application is to reduce the mutual capacitance between the frequency control line and the qubit; and the corresponding implementation means mainly include adjusting the relative position relationship between the frequency control line and the qubit from the region between the capacitor plates as shown in Figure 3 to a region far from the capacitor plates of the qubit (i.e., the frequency control line region shown in Figure 6 ).

[0075] The following will elaborate on each part of the superconducting qubit structure in the example.

[0076] For example, as shown in Figure 5 and Figure 6 , the capacitor plates 101 and 102 are of the same shape. However, in other examples, the capacitor plates 101 and 102 can also adopt different shape and structure designs.

[0077] Exemplarily, the two capacitor plates are of a rounded rectangular structure. In other examples, the two capacitor plates can also be of a rectangular structure, or a square, or other shapes, even the shape of the capacitor plates shown in Figure 2 .

[0078] Among them, the shapes of the first capacitor plate 101 and the second capacitor plate 102 are the same, but in other examples, the shapes of the first capacitor plate 101 and the second capacitor plate 102 can also be different. For example, in some examples, the shape of the first capacitor plate 101 is a rounded rectangle, and the shape of the second capacitor plate 102 is a rectangle. That is to say, there is no special limitation on the specific shapes of the two capacitor plates, as long as they meet the equivalent capacitance of the corresponding qubit.

[0079] In other examples, the area of the capacitor plates can also be selected according to needs. For example, the first capacitor plate 101 and the second capacitor plate 102 can have the same area. This can be achieved by designing the shapes and sizes of the two capacitor plates to be the same, or by designing two capacitor plates with different shapes and adjusting their sizes to achieve the same area.

[0080] Further, in Figure 6 the two capacitor plates are designed to be symmetrically distributed in the vertical direction, and the axis of symmetry is a horizontal line in the horizontal direction. However, in other examples, the two capacitor plates may also be staggered laterally with respect to each other.

[0081] Alternatively, in other examples, various appropriate selections or adjustments may also be made to the distance between the first capacitor plate 101 and the second capacitor plate 102. Moreover, the areas of the two capacitor plates and the distance between the two capacitor plates can be adaptively selected synchronously. For example, increasing the area of the capacitor plates and synchronously increasing the distance between the capacitor plates.

[0082] In Figure 6 the superconducting qubit shown, for the structure in which the Josephson junction and the qubit capacitor are connected to each other, the connection circuit includes two branches, namely, an independent first branch 201 and a second branch 202.

[0083] In some examples, the first branch 201 is integrally formed with the first capacitor plate 101, as shown in Figure 6 ; however, in other examples, the first branch 201 and the first capacitor plate 101 may also be designed as a split structure and connected by appropriate components. Integrating one of the capacitor plates and one branch of the connection circuit helps to reduce the manufacturing difficulty and improve the connection stability and effectiveness between the two.

[0084] Based on the above examples, the second branch 202 and the second capacitor plate 102 can also be designed as an integrally formed structure accordingly; or, the second branch 202 and the second capacitor plate 102 can also be designed as a split structure.

[0085] As an example of a superconducting qubit with adjustable frequency (and thus a frequency control line can be configured), Figure 5 , Figure 6 in the structure of the two-island qubit, the Josephson junction circuit 203 is a superconducting quantum interferometer and has two Josephson junctions.

[0086] For example, the superconducting quantum interferometer circuit includes a transverse circuit 303 and two longitudinal circuits. The two longitudinal circuits can be described as a first longitudinal circuit 301 and a second longitudinal circuit 302 for the convenience of discussion.

[0087] The transverse circuit 303 is connected to the first branch 201 in the connection circuit, and the transverse circuit 303 has a first end and a second end distributed at both ends in the transverse direction.

[0088] The first vertical circuit 301 and the second vertical circuit 302 in the vertical circuit are respectively connected to the second branch 202. The first vertical circuit 301 crosses the horizontal circuit 303 at the first end, and a first Josephson junction is formed at the crossing; similarly, the second vertical circuit 302 crosses the horizontal circuit 303 at the second end, and a second Josephson junction is formed at the crossing. Refer to Figure 7 .

[0089] Based on the need for convenient connection and other operational requirements, in some examples, connection components 304 can be provided in the horizontal circuit 303 and the two vertical circuits (refer to Figure 8 ) to facilitate the connection between the horizontal circuit 303 and the first branch 201, and the connection between the two vertical circuits and the second branch 202. The connection component 304 can be a structure described as a pad.

[0090] Based on the above superconducting qubit, a superconducting quantum chip can be constructed by optionally adding various circuits and components. That is, in the examples of this application, a superconducting quantum chip is disclosed, which includes superconducting qubits.

[0091] In some more specific examples, this application discloses a superconducting quantum chip, which includes a substrate.

[0092] The substrate can be high-resistance silicon or sapphire. The surface of the substrate is polished, which can be chemical mechanical polishing (CMP for short), and can also be cleaned with organic solvents to remove grease.

[0093] And a superconducting metal film (such as an aluminum film, a tantalum film, etc.) that can provide a ground plane is provided on the surface of the substrate. At the same time, through holes are formed in the superconducting metal film on the exposed surface. The through holes can be formed by etching the superconducting metal film to leave the surface of the substrate.

[0094] The superconducting qubits in the above form are arranged in the through holes of the substrate. Therefore, it can be known that the qubit distribution area of the superconducting qubits is located in the area defined by the through holes, so that the superconducting qubits are located inside the through holes.

[0095] When the superconducting metal film on the surface of the substrate is used as the ground plane; or, when a part of the superconducting metal film is used as the ground plane and at least a part of the remaining part is used to construct other components (such as coplanar waveguide transmission lines), the Josephson junction circuit 203 can be arranged in a position adjacent to the ground plane.

[0096] Furthermore, based on the need to control the frequency of the superconducting qubits, the frequency control line can be arranged near the Josephson junction. For example, Figure 6The frequency control line region shown.

[0097] In addition to the frequency control line, a pulse control signal line for superconducting qubits can also be set. Furthermore, in the superconducting quantum chip, a readout resonator for reading the quantum state of the superconducting qubits can be set as needed, and a convenient readout bus for facilitating the reading of each superconducting qubit can also be set.

[0098] Based on the above superconducting qubits and superconducting quantum chips, a quantum computer can also be disclosed. The quantum computer can also include a classical computer system, a measurement and control system (abbreviated as the measurement and control system), etc.

[0099] The superconducting quantum chip therein is, for example, arranged in a dilution refrigerator. The measurement and control system can include a signal source device located outside the dilution refrigerator. The signal source device can be used to output a DC drive signal for driving the working frequency of the qubits on the quantum chip.

[0100] Therefore, when operating the quantum computer, corresponding control signals can be generated by controlling the signal source device, thereby operating the superconducting quantum chip located in the dilution refrigerator, and the state of the superconducting qubits in the superconducting quantum chip can be obtained by detection, so as to implement corresponding quantum calculations.

[0101] For the sake of brevity, conventional techniques related to semiconductor and / or superconducting devices and integrated circuit (IC) manufacturing may be described in detail or not in this article.

[0102] In addition, the various tasks and process steps in this article can be incorporated into more comprehensive programs or processes with additional steps or functionality not described in detail in this article. In particular, the individual steps in the manufacturing of semiconductor and / or superconducting devices and semiconductor / superconductor-based ICs are well-known, so for the sake of brevity, many conventional steps will only be briefly mentioned here or will be completely omitted without providing well-known process details.

[0103] The embodiments described above by referring to the accompanying drawings are exemplary and are only used to explain the present application, and cannot be construed as a limitation to the present application.

[0104] To make the objectives, technical solutions, and advantages of the embodiments of the present application clearer, one or more embodiments are described above with reference to the accompanying drawings. Among them, similar reference numerals are used throughout the text to refer to similar components. In the above description, for the purpose of explanation, many specific details are set forth in order to provide a more thorough understanding of one or more embodiments. However, it is obvious that in various cases, one or more embodiments can be practiced without these specific details, and the various embodiments can be combined and cross-referenced with each other on the premise of not being contradictory.

[0105] It should be noted that the terms "first", "second", etc. in the description, claims and above-mentioned drawings of this application are used to distinguish similar objects, and do not necessarily need to be used to describe a specific order or sequence. It should be understood that the data used in this way can be interchanged under appropriate circumstances, so that the embodiments of this application described here can be implemented in an order other than those illustrated or described here.

[0106] In addition, the terms "comprising" and "having" and any variations thereof are intended to cover non-exclusive inclusion. For example, a process, method, system, product or device that comprises a series of steps or units does not necessarily have to be limited to those steps or units clearly listed, but may include other steps or units not clearly listed or inherent to these processes, methods, products or devices.

[0107] The structure, features and effects of this application have been described in detail based on the embodiments shown in the drawings above. The above are only the preferred embodiments of this application, but the implementation scope of this application is not limited by what is shown in the drawings. Any changes made in accordance with the concept of this application, or equivalent embodiments modified into equivalent changes, still within the spirit covered by the description and drawings, should be within the protection scope of this application.

Claims

1. A superconducting quantum bit, characterized in that: The superconducting quantum bit is defined with a bit distribution region, and includes a first region, a second region and a third region that are adjacent to each other in sequence, and the superconducting quantum bit includes: A bit capacitor, consisting of a first capacitor plate and a second capacitor plate located in a first region and spaced apart from each other; Josephson junction circuit, located in the third region; and The main body is located in the connection circuit of the second area, and both ends of the connection circuit extend to the first area and the third area respectively. One end of the connection circuit is electrically connected to the Josephson junction circuit, and the other end is electrically connected to the first capacitor plate and the second capacitor plate.

2. The superconducting quantum bit according to claim 1, characterized in that: The first capacitor plate and the second capacitor plate have the same area.

3. The superconducting quantum bit according to claim 1 or 2, characterized in that: The first capacitor plate and the second capacitor plate have the same shape.

4. The superconducting quantum bit according to claim 1, characterized in that: Josephson junction circuits include superconducting quantum interference device circuits.

5. The superconducting quantum bit according to claim 1, characterized in that: The connection circuit includes an independent first branch and a second branch; the first branch is integrally formed with a first capacitor plate, and the second branch is integrally formed with a second capacitor plate.

6. The superconducting quantum bit according to claim 5, characterized in that: Josephson junction circuits include superconducting quantum interference device circuits; The superconducting quantum interference device circuit comprises: A transverse circuit connected to the first branch has a first end and a second end distributed at two ends in the transverse direction; a first longitudinal circuit and a second longitudinal circuit respectively connected to the second branch; The first longitudinal circuit crosses the transverse circuit at the first end, and forms a first Josephson junction at the intersection; and The second longitudinal circuit crosses the transverse circuit at the second end, and forms a second Josephson junction at the intersection.

7. A superconducting quantum chip, characterized in that: A superconducting quantum bit comprising any one of claims 1 to 6.

8. A superconducting quantum chip, characterized in that: include: A substrate having a superconducting metal film provided on the surface thereof and providing a ground plane, wherein the superconducting metal film is formed with a through hole exposing a portion of the surface; as well as The superconducting quantum bit according to any one of claims 1 to 6, wherein the bit distribution area is positioned in the area defined by the through hole, so that the superconducting quantum bit is located in the through hole.

9. The superconducting quantum chip according to claim 8, characterized in that: The Josephson junction circuit is disposed adjacent to the ground plane.

10. A quantum computer, characterized in that: It comprises the superconducting quantum bit described in any one of claims 1 to 6, or the superconducting quantum chip described in any one of claims 8 to 9.

Images