Signal transmission device for quantum bits and quantum computer system

Abstract

The invention provides a signal transmission device for quantum bits and a quantum computer system. The signal transmission device comprises a transceiver circuit, a first induction circuit board, a heat insulation shell layer and a second induction circuit board. The first sensing circuit board is coupled to the transceiver circuit. The heat insulation shell layer is used for partitioning the heat insulation area. The second sensing circuit board is coupled to the quantum bit. The second induction circuit board and the quantum bits are located in the heat insulation area of the heat insulation shell layer. The transceiver circuit is located outside the thermally insulating area of the thermally insulating shell. The first induction circuit board and the second induction circuit board induce each other to generate energy change. The transceiver circuit transmits and receives signals with the quantum bits through mutual induction of the first induction circuit board and the second induction circuit board.

Description

Technical Field

[0001] The present invention relates to a quantum computer and a control signal transmission technology, and particularly to a signal transmission device for quantum bits and a quantum computer system. Background Art

[0002] A quantum computer is a device and corresponding technology that uses quantum bits (Qubits) and quantum logic therein for general-purpose computing. The concept of a quantum computer is to control quantum states and record and operate on information by measuring quantum states. A quantum bit can represent both the 0 and 1 bit states simultaneously, unlike a traditional computer device that can only record one bit of information at a time. In theory, the computing speed of a quantum computer exceeds that of current computer devices.

[0003] Currently known quantum bit technologies all need to operate in an extremely low-temperature environment, while the devices used to control quantum bits usually only work at room temperature. It is necessary to transmit control signals from the room temperature environment through the barrier of a temperature control device to the quantum bits located in the extremely low-temperature environment via a transmission line. However, in addition to transmitting signals, the transmission line itself also transmits heat energy, and the way of transmitting signals will also consume power and generate heat, reducing the efficiency of thermal insulation, resulting in an increase in the error rate of signals in the quantum bits. The interference caused by the line to the read signal may also cause a decrease in signal quality. Therefore, how to reduce the transmission of heat energy into the extremely low-temperature environment when transmitting signals is one of the research directions of current quantum bit and quantum computer technologies. Summary of the Invention

[0004] The present invention is directed to a control signal transmission device for a quantum computer, which uses the near-field coupling method to transmit signals to and from quantum bits, reducing the path of heat conduction.

[0005] According to an embodiment of the present invention, a signal transmission device for quantum bits includes a transceiver circuit, a first induction circuit board, a heat insulation shell layer, and a second induction circuit board. The first induction circuit board is coupled to the transceiver circuit. The heat insulation shell layer is used to partition a heat insulation area. The second induction circuit board is coupled to the quantum bits. The second induction circuit board and the quantum bits are located in the heat insulation area of the heat insulation shell layer. The transceiver circuit is located outside the heat insulation area of the heat insulation shell layer. The first induction circuit board and the second induction circuit board interact inductively to cause an energy change, and the transceiver circuit transmits and receives signals with the quantum bits through the mutual induction of the first induction circuit board and the second induction circuit board.

[0006] According to an embodiment of the present invention, a quantum computer system includes a computer, a signal transmission device, and qubits. The computer transmits and receives signals with the qubits through the signal transmission device. The signal transmission device includes a transceiver circuit, a first induction circuit board, a heat insulation shell layer, and a second induction circuit board. The first induction circuit board is coupled to the transceiver circuit. The heat insulation shell layer is used to partition a heat insulation area. The second induction circuit board is coupled to the qubits. The second induction circuit board and the qubits are located in the heat insulation area of the heat insulation shell layer. The transceiver circuit is located outside the heat insulation area of the heat insulation shell layer. The first induction circuit board and the second induction circuit board interact inductively to cause an energy change, and the transceiver circuit transmits and receives the signals with the qubits through the mutual induction of the first induction circuit board and the second induction circuit board.

[0007] Based on the above, in the signal transmission device for qubits and the quantum computer system according to the embodiments of the present invention, the mutual induction of two induction circuit boards is used as a near-field coupling method to transmit signals with the qubits, without using a direct coupling heat conduction path such as a transmission line to connect to the cryogenic environment where the qubits are located. Therefore, this embodiment reduces the heat conduction path, reduces the possibility of destroying the ultra-low temperature environment, and thus maintains the operation quality of the qubits. In other words, this embodiment avoids a physical connection between the cryogenic environment where the qubits are located and the external normal temperature environment directly, and thus uses spatial isolation of the heat source conduction to effectively reduce the heat energy transfer. BRIEF DESCRIPTION OF THE DRAWINGS

[0008] Figure 1 is a schematic diagram of a signal transmission device for qubits according to a first embodiment of the present invention.

[0009] Figure 2 is a schematic diagram of a quantum computer system according to a second embodiment of the present invention.

[0010] Figure 3 is a schematic diagram of a signal transmission device for qubits according to a third embodiment of the present invention.

[0011] Figure 4 is a schematic circuit diagram of a transceiver circuit, a first induction circuit board, and a second induction circuit board in the signal transmission device according to the embodiments of the present invention.

[0012] Figure 5 is a circuit structure diagram of a tuning circuit of the transceiver circuit according to the embodiments of the present invention.

[0013] Figure 6 is according to Figure 5 a simulation schematic diagram of signal transmission and reception based on the circuit structure.

[0014] Figure 7 It is a physical cross-sectional structure diagram of a signal transmission device 700 according to the fourth embodiment of the present invention. Figure 8 It is another physical structure diagram of the signal transmission device 700 according to the fourth embodiment of the present invention.

[0015] Figure 9 It is a schematic diagram of a signal transmission device for qubits according to the fifth embodiment of the present invention.

[0016] Figure 10 It is a schematic diagram of a signal transmission device 1000 for qubits according to the sixth embodiment of the present invention.

[0017] Figure 11 It is a flowchart of a signal transmission method for qubits according to various embodiments of the present invention. Detailed implementation manners

[0018] Now, reference will be made in detail to the exemplary embodiments of the present invention, and examples of the exemplary embodiments are illustrated in the accompanying drawings. Whenever possible, the same element symbols are used in the drawings and the description to represent the same or similar parts.

[0019] In order to maintain the extremely low temperature environment where the qubits are located and avoid damaging the heat insulation of this extremely low temperature environment, the embodiments of the present invention use two induction circuit boards (such as, induction coils or similar circuit structures) to mutually transmit and receive signals with the qubits located in the extremely low temperature environment through near-field communication or near-field coupling, so as to prevent the qubits from directly contacting the outside environment through transmission lines. In other words, the embodiments of the present invention use near-field communication or near-field coupling to isolate the conduction of heat sources as much as possible. And, compared with the far-field wireless transmission method, the embodiments of the present invention also have less mutual interference between qubits. Further, the induction circuit board can be disposed on the inner layer of the heat insulation housing, which can save more installation space for erecting the signal transmission device. The following presents various signal transmission devices, quantum computer systems, and their circuit architectures applied to quantum computers as the embodiments of the present invention. Those who apply this embodiment can extend the following embodiments according to their needs to other implementation manners that conform to the present invention.

[0020] Figure 1 It is a schematic diagram of a signal transmission device 100 for qubits according to the first embodiment of the present invention. The signal transmission device 100 belongs to a part of the quantum computer system. The signal transmission device 100 for qubits 150 includes a transceiver circuit 110, a first induction circuit board 120, at least one heat insulation layer board (in this embodiment, the heat insulation layer boards 130-1 to 130-N are taken as examples), and a second induction circuit board 140. The first induction circuit board 120 is coupled to the transceiver circuit 110. The second induction circuit board 140 is coupled to the qubits 150.

[0021] The thermal insulation layers 130-1 to 130-N are used to partition the thermal insulation regions. Since the qubits 150 operate in an extremely low-temperature environment, the quantum computer system and the signal transmission device 100 of this embodiment utilize multiple layers of thermal insulation layers 130-1 to 130-N to gradually perform thermal isolation to maintain a specific temperature. Its structure is similar to that of a multi-layer refrigerator or Dewar flask, which uses a multi-layer vacuum structure to maintain a low temperature inside. In this embodiment, the predicted temperature value of the thermal insulation region can be 1K (-272.15 °C), and the temperature in the aforementioned thermal insulation region will be much lower than 1K (-272.15 °C). Those applying this embodiment can correspondingly set and adjust this default temperature value according to the temperature used to set the qubits in the current technology. This default temperature value is not limited only to the aforementioned example. The material of the thermal insulation layers 130-1 to 130-N can be ceramics.

[0022] The second induction circuit board 140 and the qubits 150 of this embodiment are located in the thermal insulation regions of the thermal insulation layers 130-1 to 130-N. The transceiver circuit 110 is located outside the thermal insulation regions of the thermal insulation layers 130-1 to 130-N. Figure 1 The first induction circuit board 120 can be disposed on the thermal insulation layer 130-1 (for example, at the inner layer of the thermal insulation layer 130-1), as Figure 1 shown. In another embodiment consistent with the present invention, Figure 1 the first induction circuit board 120 can be disposed in the thermal insulation regions of the thermal insulation layers 130-1 to 130-N.

[0023] The first induction circuit board 120 and the second induction circuit board 140 interact inductively to cause an energy change, as shown by the dashed arrow 135. The first induction circuit board 120 and the second induction circuit board 140 do not directly contact each other, or there is a medium (such as air or a non-conductive thermal insulation material, etc.) between the first induction circuit board 120 and the second induction circuit board 140. The transceiver circuit 110 transmits and receives signals with the qubits 150 through the mutual induction of the first induction circuit board 120 and the second induction circuit board 140. Specifically, the transceiver circuit 110 transmits and receives signals with the qubits 150 through the mutual induction of the first induction circuit board 120 and the second induction circuit board 140 using near-field communication or near-field coupling methods. In the corresponding technology consistent with the embodiments of the present invention, the first induction circuit board 120 and the second induction circuit board 140 can achieve "mutual induction" to transmit signals through induction coils, antennas, capacitive coupling, etc.

[0024] Figure 2 is a schematic diagram of a quantum computer system 200 according to the second embodiment of the present invention. The quantum computer system 200 of this embodiment further includes Figure 1In addition to the various components of the signal transmission device 100, it also includes a computer 210 and a heat insulator 220. The computer 210 transceives signals with the qubit 150 through the signal transmission device 100. Specifically, the computer 210 can provide a read signal to the transceiver circuit 110, and transmit the read input signal in the read signal to the qubit 150 through the transceiver circuit 110, the first induction circuit board 120, and the second induction circuit board 140. The read output signal of the qubit can also be transmitted to the computer 210 through the transceiver circuit 110, the first induction circuit board 120, and the second induction circuit board 140. The heat insulator 220 is used to further isolate heat energy and prevent heat conduction.

[0025] Figure 3 It is a schematic diagram of a signal transmission device 300 for qubits according to the third embodiment of the present invention. Figure 3 Similar to Figure 1 except that Figure 3 The first induction circuit board 320 in the signal transmission device 300 is disposed in the heat insulation area of the heat insulation shell layer 130-1, rather than on the heat insulation shell layer 130-1. Specifically, the first induction circuit board 320 can be disposed in the inner layer or a more internal area of the heat insulation shell layer 130-1. The transceiver circuit 110 is disposed in the outer layer or a more external area of the heat insulation shell layer 130-N. The transceiver circuit 110 is coupled to the first induction circuit board 320 through one or more through holes VIA penetrating the heat insulation shell layers 130-1 to 130-N to transmit signals to each other. In other embodiments in line with the present invention, the signal transmission manner between the transceiver circuit 110 and the first induction circuit board 320 can also be achieved through near-field coupling. For example, Figure 3 Two additional induction circuit boards are provided between the transceiver circuit 110 and the first circuit board 320 to transmit signals.

[0026] Figure 4 It is a schematic diagram of the circuit structures of the transceiver circuit 410, the first induction circuit board 420, and the second induction circuit board 440 in the signal transmission device according to the embodiments of the present invention. The transceiver circuit 410 of this embodiment includes a read input circuit 412, a read output circuit 415, and a tuning circuit 417. The read input circuit 412 can provide the read input signal provided by the computer to the first induction circuit board 420. The read output circuit 415 can obtain the read output signal from the first induction circuit board 420, and this read output signal is generated based on the data in the qubit 150.

[0027] The first induction circuit board 420 and the second induction circuit board 440 of this embodiment can be implemented with a duplex structure based on a transformer for two-way transmission. As Figure 4As shown, the first induction circuit board 420 includes a read input terminal Ew, a balance terminal Eb, a read output terminal Er, a first inductor L1, and a second inductor L2. The first end of the first inductor L1 serves as the read input terminal Ew, and the second end of the first inductor L1 is coupled to the balance terminal Eb. The first end of the second inductor L2 is coupled to the balance terminal Eb, and the second end of the second inductor L2 is coupled to the read output terminal Er. The read input terminal Ew is coupled to the read input circuit 412. The balance terminal Eb is coupled to the tuning circuit 417, and the read output terminal Er is coupled to the read output circuit 415. The read input terminal Ew, the balance terminal Eb, and the read output terminal Er respectively correspond to a plurality of through holes of the aforementioned heat insulation shell layers 130-1 to 130-N. The read input circuit 412, the read output circuit 415, and the tuning circuit 417 are respectively electrically connected to the read input terminal Ew, the read output terminal Er, and the balance terminal Eb of the first inductor L1 through these through holes. The second induction circuit board 440 includes a third inductor L3. The first end of the third inductor L3 is coupled to the qubit 150. The second end of the third inductor L3 is coupled to a reference voltage terminal (e.g., ground terminal GND).

[0028] The tuning circuit 417 is used to control and adjust the impedance of the first induction circuit board 420, thereby adjusting the signal frequency of the read input signal or the read output signal. In this embodiment, the tuning circuit 417 is exemplified by an electrical balance duplexer. Figure 5 It is a circuit structure diagram of the tuning circuit of the transceiver circuit 410 according to various embodiments of the present invention. Figure 5 The tuning circuit 517 of includes a resistor Rbal and a capacitor Cbal. The first end of the resistor Rbal is coupled to the balance terminal Eb. The second end of the resistor Rbal is coupled to a reference voltage terminal (ground terminal GND). The first end of the capacitor Cbal is coupled to the balance terminal Eb. The second end of the capacitor Cbal is coupled to a reference voltage terminal (ground terminal GND). In accordance with various embodiments of the present invention, the resistor Rbal and the capacitor Cbal can be resistors and capacitors with fixed values to form a fixed resistor-capacitor circuit through broadband impedance design. In accordance with another embodiment of the present invention, the resistor Rbal and the capacitor Cbal can be a variable resistor and a variable capacitor respectively, and the aforementioned variable resistor and variable capacitor can be controlled by other control circuits of the transceiver circuit 410 to perform impedance modulation and be suitable for transceiver signals.

[0029] Figure 6 is in accordance with Figure 5 An analog schematic diagram of transceiver signals according to the circuit structure of. It can be seen from the simulation diagram of the aforementioned circuit structure in the embodiment of the present invention that when the tuning circuit 517 is a fixed resistor-capacitor circuit, frequencies at approximately 1.7, 1.9, and 2.05 GHz can enable the transceiver circuit and the qubit to mutually transceiver signals.

[0030] Figure 7 It is a physical cross-sectional structure diagram of the signal transmission device 700 according to the fourth embodiment of the present invention. Figure 8 It is another physical structure diagram of the signal transmission device 700 according to the fourth embodiment of the present invention. The fourth embodiment of the present invention details the method of implementing the first induction circuit board 720 and the second induction circuit board 740, while referring to Figure 7 and Figure 8 , the first induction circuit board 720 includes a substrate 722 and a circuit 725. The substrate 722 can be a partial area of the aforementioned heat insulation shell layer (such as Figure 1 the heat insulation shell layer 130-1). The circuit 725 of the first induction circuit board 720 is disposed on the inner layer of the heat insulation shell layer (substrate 722), and the transceiver circuit 410 (such as, the read input circuit 412, the read output circuit 415, and the tuning circuit 417) is disposed on the outer layer of the heat insulation shell layer (substrate 722). The transceiver circuit 410 is coupled to the circuit 725 of the first induction circuit board 720 through through-holes (such as, through-holes corresponding to the read input terminal Ew, the balance terminal Eb, and the read output terminal Er) that penetrate the heat insulation shell layer (substrate 722).

[0031] The second induction circuit board 740 includes a substrate 742 and a circuit 745. The quantum bit 150 can be disposed on one side of the substrate 742, and the circuit 745 can be disposed on the other side of the substrate 742.

[0032] Figure 9 It is a schematic diagram of a signal transmission device 900 for quantum bits according to the fifth embodiment of the present invention. Figure 9 and Figure 1 The difference is that the signal transmission device 900 further includes an analog interference cancellation circuit AIC 960 disposed between the transceiver circuit 110 and the first induction circuit board 120. The AIC 960 utilizes the characteristics of analog circuits and corresponding components to reduce interference from the read input path (such as, the read input circuit). The analog interference cancellation circuit AIC 960 can also be applied to other embodiments of the present invention. For example, the analog interference cancellation circuit AIC 960 can also be applied to Figure 3 the signal transmission device 300.

[0033] Figure 10 It is a schematic diagram of a signal transmission device 1000 for quantum bits according to the sixth embodiment of the present invention. Figure 10 and Figure 9The difference is that in addition to the analog interference cancellation circuit AIC 960, the signal transmission device 1000 further includes a digital interference cancellation circuit DIC 1070 coupled to the transceiver circuit. The DIC 1070 uses digital circuits to reduce interference from the read input path. The digital interference cancellation circuit DIC 1070 can also be applied to other embodiments of the present invention. For example, the digital interference cancellation circuit DIC 1070 can also be applied to Figure 3 the signal transmission device 300.

[0034] Figure 11 is a flowchart of a signal transmission method for qubits according to various embodiments of the present invention. Figure 11 The signal transmission method is used in each signal transmission device of the embodiments of the present invention. Here, Figure 1 the signal transmission device 100 is taken as an example. Please also refer to Figure 1 and Figure 11 . In step S1110, the computer provides a read input signal to the transceiver circuit 110. The transceiver circuit 110 is coupled to the first induction circuit board 120, and the qubit 150 is coupled to the second induction circuit board 140. In step S1120, based on the mutual induction of the transceiver device 110 through the first induction circuit board 120 and the second induction circuit board 140, the read input signal is provided to the qubit 150. In step S1130, based on the mutual induction of the transceiver device 110 through the first induction circuit board 120 and the second induction circuit board 140, the read output signal of the qubit 150 is obtained. For the corresponding steps and detailed operations of the signal transmission method, please refer to the foregoing embodiments.

[0035] In summary, the signal transmission device for qubits and the quantum computer system described in the embodiments of the present invention use the mutual induction of two induction circuit boards as a near-field coupling method to transmit signals to the qubits, without using a direct coupling heat conduction path such as a transmission line to connect to the cryogenic environment where the qubits are located. Therefore, this embodiment reduces the heat conduction path, reduces the possibility of destroying the ultra-low temperature environment, and thus maintains the operation quality of the qubits. In other words, this embodiment avoids a direct physical connection between the cryogenic environment where the qubits are located and the external normal temperature environment, and thus uses spatial isolation of heat source conduction to effectively reduce heat energy transfer.

[0036] Finally, it should be noted that: the above embodiments are only used to illustrate the technical solutions of the present invention, and are not intended to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that: they can still modify the technical solutions described in the foregoing embodiments, or perform equivalent replacements on some or all of the technical features; and these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A signal transmission device for quantum bits, characterized in that: include: transceiver circuit; A first sensing circuit board coupled to the transceiver circuit; A heat-insulating shell layer is used to separate the heat-insulating area; as well as A second sensing circuit board is coupled to the quantum bit, The second sensing circuit board and the quantum bit are located in the heat-insulating area of ​​the heat-insulating shell, and the transceiver circuit is located outside the heat-insulating area of ​​the heat-insulating shell. The first sensing circuit board and the second sensing circuit board sense each other to generate energy changes, and the transceiver circuit receives and sends signals to the quantum bit through the mutual induction of the first sensing circuit board and the second sensing circuit board.

2. The signal transmission device according to claim 1, characterized in that: The first sensing circuit board is disposed in the heat insulating region of the heat insulating shell layer.

3. The signal transmission device according to claim 1, characterized in that: The first sensing circuit board is arranged on the heat-insulating shell layer.

4. The signal transmission device according to claim 1, characterized in that: The transceiver circuit comprises: A reading input circuit, providing a reading input signal to the first sensing circuit board; A read output circuit, which obtains a read output signal from the first sensing circuit board; and The tuning circuit is used to control and adjust the impedance of the first sensing circuit board to adjust the frequency of the read input signal or the read output signal.

5. The signal transmission device according to claim 4, characterized in that: The first induction circuit board comprises: a first inductor, wherein a first end of the first inductor serves as a read input end, and a second end of the first inductor is coupled to a balanced end, wherein the read input end is coupled to the read input circuit, and the balanced end is coupled to the tuning circuit; and A second inductor, wherein a first terminal of the second inductor is coupled to the balanced terminal, and a second terminal of the second inductor is coupled to a read output terminal, wherein the read output terminal is coupled to the read output circuit.

6. The signal transmission device according to claim 5, characterized in that: The read input end, the balance end and the read output end correspond to a plurality of through holes of the thermal insulation shell layer respectively.

7. The signal transmission device according to claim 5, characterized in that: The second sensing circuit board includes a third inductor, a first end of the third inductor is coupled to the quantum bit, and a second end of the third inductor is coupled to a reference voltage end.

8. The signal transmission device according to claim 4, characterized in that: The tuned circuit is an electrically balanced duplexer.

9. The signal transmission device according to claim 5, characterized in that: The tuning circuit comprises: a resistor, a first end of the resistor being coupled to the balance end, and a second end of the resistor being coupled to the reference voltage end; and A capacitor, a first end of the capacitor is coupled to the balance end, and a second end of the resistor is coupled to the reference voltage end.

10. The signal transmission device according to claim 9, characterized in that: The resistor is a variable resistor, and the capacitor is a variable capacitor.

11. The signal transmission device according to claim 1, characterized in that: The first sensing circuit board is arranged on the inner layer of the heat-insulating shell layer, the transceiver circuit is arranged on the outer layer of the heat-insulating shell layer, and the transceiver circuit is coupled to the first sensing circuit board through a through hole penetrating the heat-insulating shell layer.

12. The signal transmission device according to claim 1, characterized in that: The transceiver circuit transmits and receives signals with the quantum bit by using near-field coupling through mutual induction between the first sensing circuit board and the second sensing circuit board.

13. The signal transmission device according to claim 1, characterized in that: The first induction circuit board and the second induction circuit board respectively include induction coils.

14. The signal transmission device according to claim 1, characterized in that: Also includes: The analog interference elimination circuit is coupled between the transceiver circuit and the first sensing circuit board to reduce interference in the read input path.

15. The signal transmission device according to claim 1, characterized in that: The digital interference elimination circuit is coupled to the transceiver circuit to reduce interference of a read input path.

16. A quantum computer system, characterized in that: include: computer; a signal transmission device, coupled to the computer; as well as Quantum bits, wherein the computer sends and receives signals with the quantum bit through the signal transmission device, The signal transmission device comprises: transceiver circuit; A first sensing circuit board coupled to the transceiver circuit; Insulation shells to separate insulation areas; and A second sensing circuit board is coupled to the quantum bit, The second sensing circuit board and the quantum bit are located in the heat-insulating area of ​​the heat-insulating shell, and the transceiver circuit is located outside the heat-insulating area of ​​the heat-insulating shell. The first sensing circuit board and the second sensing circuit board sense each other to generate energy changes, and the transceiver circuit transmits and receives the signal with the quantum bit through the mutual induction of the first sensing circuit board and the second sensing circuit board.

17. The quantum computer system according to claim 16, characterized in that: The first sensing circuit board is disposed in the heat insulating region of the heat insulating shell layer.

18. The quantum computer system according to claim 16, characterized in that: The transceiver circuit comprises: A reading input circuit, providing a reading input signal to the first sensing circuit board; A read output circuit, which obtains a read output signal from the first sensing circuit board; and The tuning circuit is used to control and adjust the impedance of the first sensing circuit board to adjust the frequency of the read input signal or the read output signal.

19. The quantum computer system according to claim 18, characterized in that: The tuning circuit comprises: a resistor, wherein a first end of the resistor is coupled to the balance end, and a second end of the resistor is coupled to the reference voltage end; and A capacitor, a first end of the capacitor is coupled to the balance end, and a second end of the resistor is coupled to the reference voltage end.

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