Superconducting qubit control device

Abstract

The present application discloses a quantum bit control device, which is applied to the field of quantum computing. The device includes a first coupling device, a second coupling device, at least one signal extraction device, and a quantum chip located in the second temperature zone. The first coupling device is configured to receive multiple mixing control signals with different frequencies from a first transmission medium and send them to the signal extraction device. The second coupling device is configured to receive a local oscillator signal from a second transmission medium and send it to the signal extraction device, wherein the mixing control signal and the local oscillator signal are generated in a first temperature zone, and the temperature of the first temperature zone is higher than that of the second temperature zone. The signal extraction device filters the received mixing control signal and local oscillator signal, and down-converts the filtered control signal and the filtered local oscillator signal to recover the control signal for manipulating the quantum bits in the quantum chip. This embodiment can reduce the heat transfer to the superconducting quantum chip and simultaneously reduce the wiring difficulty on the superconducting quantum chip.

Description

Technical Field

[0001] The present application relates to the field of quantum computing technology, and particularly to a control device for superconducting qubits. Background Art

[0002] A quantum computer is a device that performs general computing using quantum logic. Its special feature is that the superposition property of quantum states enables large-scale "parallel" computing. Based on this, special quantum algorithms can be designed, enabling the solution of certain problems to be exponentially accelerated, thus solving problems that are difficult for traditional computers to solve in a short time. For example, prime factor decomposition of large numbers, combinatorial optimization problems, etc. With the progress of theoretical research, new quantum algorithms are constantly being proposed to accelerate the solution of different problems.

[0003] The basic unit of a quantum computer is a qubit, and various quantum algorithms perform different quantum operations on different numbers of qubits. A qubit is like a semiconductor logic gate on a traditional computer. The more qubits there are, the stronger its parallel acceleration ability, and the faster the solution speed for the same problem. There are multiple physical systems that can be used to construct qubits, such as superconducting circuits, ion traps, semiconductor quantum dots, topological quantum computing, etc. Among them, superconducting circuits are a relatively popular system.

[0004] The basic unit of superconducting quantum computing is a superconducting quantum chip, which needs to work in an ultra-low temperature environment (~10mK level). Ultra-low temperature can effectively reduce the influence of environmental noise. Therefore, cryogenic refrigeration technology is a key technology for superconducting quantum computing. Currently, the commonly used refrigeration device is a (helium-free) dilution refrigerator, which adopts a hierarchical refrigeration technology. In the ultra-low temperature region, the phase change endotherm of helium element is used for further refrigeration, so that the lowest temperature region can be cooled to the 10mK level. Figure 1 Shows the basic structure of a common dilution refrigerator. The cold plate in the lowest temperature region needs to reach a temperature below 20mK, and the quantum chip is usually located Figure 1 in the sample chamber shown.

[0005] In order to manipulate the qubits on the quantum chip, electrical signals need to be introduced into the bottommost sample chamber. The signal lines for these control signals will pass through different cold plates layer by layer (see Figure 1(Schematic diagram of signal cables), attenuation and temperature reduction are carried out at each cold plate to reduce heat transfer to the chip in the sample chamber. Controlling the heat conduction of the signal line is the largest input heat source of the entire cold plate. In the current solution, at least one control signal line is required for each qubit. If adjustable coupling is considered, two additional signal lines are required. Therefore, under the existing dilution refrigerator structure, the number of superconducting qubits it can support has an upper limit. As the number of qubits increases, when the heat conduction power experienced on a certain cold plate is greater than its refrigeration power, the number of qubits can no longer increase. Therefore, reducing the actual number of cables used or reducing the heat transfer power of a single cable is a problem that the measurement and control system will soon face.

[0006] On the other hand, when the scale of the number of qubits in the superconducting qubit chip increases, there will also be a wiring problem. Specifically, each superconducting qubit requires an independent control signal. In the currently common chip structures, on average, 3 to 4 control lines are required per qubit. One end of this control line is adjacent to the superconducting qubit, and the other end is connected to the edge of the chip. At the edge, it is enlarged into a larger conductive area, and this area will be used as the bonding pad for connecting the chip and the external circuit lead. The size of a single bonding pad is usually in the range of 50um to 500um and is arranged at the outermost edge of the chip. The connection of large-scale superconducting qubits is not just a single-chain type. In fact, currently, a two-dimensional planar distribution is more commonly used, such as Figure 2 The square lattice arrangement shown on the left, where each superconducting qubit will be connected to the four qubits above, below, left, and right. In such a two-dimensional arrangement structure, when the chip size increases, the number of superconducting qubits that can be accommodated in the qubit area increases quadratically (proportional to the area), but the number of bonding areas for leads only increases linearly (proportional to the perimeter). Considering that the chip area has a limit and cannot be arbitrarily large, this contradiction will in turn limit the maximum number of qubits that can be accommodated in a single chip. It can be predicted that when the number of qubits increases significantly, there will be a problem of insufficient space in the layout of the bonding areas of the control lines on the chip.

[0007] In view of the above problems, the present patent technology proposes a new superconducting qubit control device, which can effectively reduce the heat conduction power of the cable to the chip and reduce the number of bonding areas on the chip, thereby increasing the number of qubits that can be accommodated in a single chip and realizing system expansion. Summary of the Invention

[0008] The present application provides a qubit control device, which solves the problem that the number of qubits is limited due to heat conduction and insufficient space in the bonding area of the control line in the prior art.

[0009] In the first aspect, a qubit control device is provided. The qubit control device includes a first coupling device, a second coupling device, at least one signal extraction device, and a quantum chip located in the second temperature zone;

[0010] The first coupling device is configured to receive a plurality of mixing control signals from a first transmission medium and send the mixing control signals to the signal extraction device, wherein each mixing control signal has a different frequency;

[0011] The second coupling device is configured to receive a local oscillator signal from a second transmission medium and send the local oscillator signal to the signal extraction device, wherein the mixing control signal and the local oscillator signal are generated in a first temperature region, and the temperature of the first temperature region is higher than that of the second temperature region;

[0012] The signal extraction device includes: a first filtering and receiving device, a second filtering and receiving device, and a first mixer;

[0013] The first filtering and receiving device is configured to filter the received mixing control signal and send the obtained filtered control signal to the first mixer;

[0014] The second filtering and receiving device is configured to filter the received local oscillator signal and send the obtained filtered local oscillator signal to the first mixer;

[0015] The first mixer is configured to down-convert the filtered control signal and the filtered local oscillator signal to recover the control signal, and send the control signal to the quantum chip, wherein the control signal is used to manipulate quantum bits in the quantum chip.

[0016] In the embodiment of the present application, the mixing control signals are transmitted through frequency division multiplexing technology, and down-conversion is performed on the mixing control signals in a low-temperature region, so that the obtained control signals conform to the working frequencies of the corresponding quantum bits, achieving the effect of manipulating the quantum bits. This method can reduce the number of signal transmission cables from a high-temperature region to a low-temperature region, reduce heat transfer caused by the cables, and also alleviate the wiring problem on the quantum chip.

[0017] Combined with the first aspect, in the first possible implementation manner of the first aspect, the first coupling device is an antenna or a near-field coupling structure; the second coupling device is an antenna or a near-field coupling structure. Transmitting the mixing control signals through an antenna can reduce the number of transmission lines on the chip and more effectively solve the wiring problem; transmitting the mixing control signals through a near-field coupling structure has lower loss compared with the antenna method.

[0018] Taking the first coupling device and the second coupling device as examples, several specific structures are given below.

[0019] Combined with the first possible implementation manner of the first aspect, in the second possible implementation manner of the first aspect, the first coupling device is a first antenna for broadcasting the received mixing control signal; the second coupling device is a second antenna for broadcasting the received local oscillator signal;

[0020] The first filtering and receiving device includes a first receiving antenna and a first filter. The first receiving antenna is used to receive the mixing control signal and send the mixing control signal to the first filter; the first filter is used to filter the mixing control signal and send the obtained filtered control signal to the first mixer;

[0021] The second filtering and receiving device includes a second receiving antenna and a second filter. The second receiving antenna is used to receive the local oscillator signal and send the local oscillator signal to the second filter; the second filter is used to filter the local oscillator signal and send the obtained filtered local oscillator signal to the first mixer.

[0022] Combined with the first possible implementation manner of the first aspect, in the third possible implementation manner of the first aspect, the first coupling device is a first antenna for broadcasting the received mixing control signal; the second coupling device is a second antenna for broadcasting the received local oscillator signal; the signal extraction device includes N first mixers, where N is an integer greater than 1;

[0023] The first filtering and receiving device includes a third receiving antenna, a first power splitter, and N third filters. The third receiving antenna is used to receive the mixing control signal and send the mixing control signal to the first power splitter; the first power splitter is used to divide the mixing control signal into N paths and send them to the N third filters respectively; the third filter is used to filter one path of the received mixing control signal and send the obtained filtered control signal to the corresponding first mixer; where each third filter is connected to a different first mixer;

[0024] The second filtering and receiving device includes a fourth receiving antenna, a second power splitter, and N fourth filters. The fourth receiving antenna is used to receive the local oscillator signal and send the local oscillator signal to the second power splitter; the second power splitter is used to divide the local oscillator signal into N paths and send them to the N fourth filters respectively; the fourth filter is used to filter one path of the received local oscillator signal and send the obtained filtered local oscillator signal to the corresponding first mixer; where each fourth filter is connected to a different first mixer.

[0025] Combined with the first possible implementation manner of the first aspect, in the fourth possible implementation manner of the first aspect, the first coupling device is a first antenna for broadcasting the received mixing control signal; the second coupling device is a second antenna for broadcasting the received local oscillator signal; the signal extraction device includes N first filtering and receiving devices and N first mixers, where N is an integer greater than 1;

[0026] The first filtering and receiving device includes a first receiving antenna and a first filter. The first receiving antenna is used to receive the mixing control signal and send the mixing control signal to the first filter; the first filter is used to filter the mixing control signal and send the obtained filtered control signal to the corresponding first mixer;

[0027] The second filtering and receiving device includes a fourth receiving antenna, a second power splitter, and N fourth filters. The fourth receiving antenna is used to receive the local oscillator signal and send the local oscillator signal to the second power splitter; the second power splitter is used to divide the local oscillator signal into N paths and send them to the N fourth filters respectively; the fourth filter is used to filter one path of the received local oscillator signal and send the obtained filtered local oscillator signal to the corresponding first mixer; where each fourth filter is connected to a different first mixer.

[0028] Combined with the first possible implementation manner of the first aspect, in the fifth possible implementation manner of the first aspect, the first coupling device is a first antenna for broadcasting the received mixing control signal; the second coupling device is a second antenna for broadcasting the received local oscillator signal; the signal extraction device includes N second filtering and receiving devices and N first mixers, where N is an integer greater than 1;

[0029] The first filtering and receiving device includes a third receiving antenna, a first power splitter, and N third filters. The third receiving antenna is used to receive the mixing control signal and send the mixing control signal to the first power splitter; the first power splitter is used to divide the mixing control signal into N paths and send them to the N third filters respectively; the third filter is used to filter one path of the received mixing control signal and send the obtained filtered control signal to the corresponding first mixer; where each third filter is connected to a different first mixer;

[0030] The second filtering and receiving device includes a second receiving antenna and a second filter. The second receiving antenna is configured to receive the local oscillator signal and send the local oscillator signal to the second filter. The second filter is configured to filter the local oscillator signal and send the filtered local oscillator signal to the first mixer.

[0031] Combined with the above possible implementation manners, in the sixth possible implementation manner of the first aspect, the first transmission medium is a coaxial cable or a dielectric waveguide; the second transmission medium is a coaxial cable or a dielectric waveguide, responsible for high-frequency signal transmission.

[0032] Combined with the first possible implementation manner of the first aspect, in the seventh possible implementation manner of the first aspect, the first coupling device is a first near-field coupling structure or a first cable connector, configured to couple the mixing control signal received from the first transmission medium to the signal extraction device; the second coupling device is a second near-field coupling structure or a second cable connector, configured to couple the local oscillator signal received from the second transmission medium to the signal extraction device; the first filtering and receiving device is configured to divide the received mixing control signal into M paths, filter each path respectively, and send the obtained M filtered control signals to the corresponding first mixers, where the frequencies of each filtered control signal are different, and M is an integer greater than 1; the second filtering and receiving device is configured to divide the received local oscillator signal into M paths, filter each path respectively, and send the obtained M filtered local oscillator signals to the corresponding first mixers.

[0033] Combined with the seventh possible implementation manner of the first aspect, in the eighth possible implementation manner of the first aspect, the first filtering and receiving device includes a third power divider and M fifth filters. The third power divider is configured to divide the mixing control signal into M paths and send them to the M fifth filters respectively. The fifth filter is configured to filter one path of the received mixing control signal and send the obtained filtered control signal to the corresponding first mixer. Each fifth filter is connected to a different first mixer. The second filtering and receiving device includes a fourth power divider and M sixth filters. The fourth power divider is configured to divide the local oscillator signal into M paths and send them to the M sixth filters respectively. The sixth filter is configured to filter one path of the received local oscillator signal and send the obtained filtered local oscillator signal to the corresponding first mixer. Each sixth filter is connected to a different first mixer.

[0034] Combined with the above possible implementation manners, in the ninth possible implementation manner of the first aspect, there are multiple first coupling devices, and the signals output by each first coupling device are used to control the qubits in different regions of the quantum chip. In this embodiment, each coupling device is responsible for a different region, which can adapt to the further growth of the number of qubits in the future.

[0035] Combined with the above possible implementation manners, in the tenth possible implementation manner of the first aspect, the signal extraction device further includes a signal filter, which is used to receive the signal output by the first mixer, filter out the high-frequency part of the output signal, and recover the control signal to improve the accuracy of the control signal. The signal filter corresponds to the first mixer one by one.

[0036] Combined with the above possible implementation manners, in the eleventh possible implementation manner of the first aspect, one first mixer corresponds to one qubit. Optionally, it is possible that one qubit requires multiple control signals, and in this case, it may correspond to multiple first mixers.

[0037] Combined with the above possible implementation manners, in the twelfth possible implementation manner of the first aspect, the signal extraction device and the qubit are integrated on the same layer of the quantum chip; they can also be integrated on different layers of the quantum chip. When integrated on different layers, there is a shielding structure or shielding layer between the layer where the signal extraction device is located and the layer where the qubit is located, reducing the influence of interference signals on the manipulation of the qubit.

[0038] Combined with the above possible implementation manners, in the thirteenth possible implementation manner of the first aspect, the first mixer is a Superconductor-Insulator-Superconductor (SIS) mixer or a Hot Electron Bolometer (HEB) mixer.

[0039] Combined with the above possible implementation manners, in the sixteenth possible implementation manner of the first aspect, the qubit control device further includes a control signal generator, a local oscillator signal generator, a second mixer, and a combiner located in the first temperature zone; the control signal generator and the local oscillator signal generator are respectively connected to the second mixer, where one control signal and one local oscillator signal form a group, and there are at least two groups, and the sum of the frequencies of the control signal and the local oscillator signal in each group is different; the second mixer is configured to perform up-conversion on the control signal and the local oscillator signal in each group to obtain a plurality of mixing control signals with different frequencies; the combiner is configured to receive the mixing control signals, combine the plurality of mixing control signals into one path, and send them to the second coupling device through a first transmission medium, where the mixing control signal is used to manipulate the qubits in the quantum chip. Optionally, the frequencies of the control signals in each group are different, and / or the frequencies of the local oscillator signals in each group are different.

[0040] In a second aspect, a qubit control method is provided, and the method includes: receiving a plurality of mixing control signals from a first transmission medium in a second temperature zone; receiving a local oscillator signal from a second transmission medium in the second temperature zone, where the mixing control signal and the local oscillator signal are generated in a first temperature zone, and the temperature of the first temperature zone is higher than that of the second temperature zone; filtering the mixing control signals; filtering the local oscillator signals; performing down-conversion on the filtered control signals and the filtered local oscillator signals to recover the control signals for manipulating the qubits in the quantum chip, where the filtered control signals and the filtered local oscillator signals are both multiple and correspond one by one.

[0041] In the embodiment of the present application, the mixing control signals are transmitted through frequency division multiplexing technology, and down-conversion is performed on the mixing control signals in the low-temperature zone, so that the obtained control signals conform to the working frequencies of the corresponding qubits, achieving the effect of manipulating the qubits. This method can reduce the number of signal transmission cables from the high-temperature zone to the low-temperature zone, reduce the heat transfer caused by the cables, and also relieve the wiring problem on the quantum chip.

[0042] Combined with the second aspect, in the first possible implementation manner of the second aspect, after receiving the plurality of mixing control signals from the first transmission medium, the method further includes: dividing the mixing control signals into N paths, and respectively filtering the N paths of mixing control signals, where N is an integer greater than 1.

[0043] Combined with the second aspect or the first possible implementation manner of the second aspect, in the second possible implementation manner of the second aspect, after receiving the local oscillator signal from the second transmission medium, the method further includes: dividing the local oscillator signal into N paths, and respectively filtering the N paths of local oscillator signals, where N is an integer greater than 1.

[0044] Combined with the second aspect or any possible implementation manner of the second aspect, in the third possible implementation manner of the second aspect, the first transmission medium is a coaxial cable or a dielectric waveguide; the second transmission medium is a coaxial cable or a dielectric waveguide, which is responsible for the transmission of high-frequency signals.

[0045] Combined with the second aspect or any possible implementation manner of the second aspect, in the fourth possible implementation manner of the second aspect, the mixing control signal is received by means of broadcast radiation or near-field coupling; and / or the local oscillator signal is received by means of broadcast radiation or near-field coupling. Transmitting the mixing control signal by means of broadcast radiation can reduce the number of transmission lines on the chip and more effectively solve the wiring problem; transmitting the mixing control signal by means of near-field coupling has lower loss compared with the broadcast radiation method.

[0046] Combined with the second aspect or any possible implementation manner of the second aspect, in the fifth possible implementation manner of the second aspect, after down-converting the filtered control signal and the filtered local oscillator signal, the method further includes: filtering the down-converted signal to filter out the high-frequency part of the signal, recovering the control signal, and reducing the influence of high-frequency signals on the quantum manipulation accuracy.

[0047] Combined with the second aspect or any possible implementation manner of the second aspect, in the sixth possible implementation manner of the second aspect, before receiving the mixing control signal and the local oscillator signal, the method further includes: generating a control signal and a local oscillator signal in a first temperature region, where one control signal and one local oscillator signal form a group, and there are at least two groups, and the sum of the frequencies of the control signal and the local oscillator signal in each group is different; up-converting the control signal and the local oscillator signal in each group to obtain a plurality of mixing control signals with different frequencies; combining the plurality of mixing control signals into one path and sending them to a quantum chip located in a second temperature region through a first transmission medium.

[0048] Optionally, the frequencies of the control signals in each group are different, and / or the frequencies of the local oscillator signals in each group are different.

[0049] In a third aspect, a quantum bit control device is provided, and the quantum bit control device further includes a first coupling device and at least one signal extraction device located in a second temperature region;

[0050] The first coupling device is configured to receive a plurality of mixing control signals with different frequencies from a first transmission medium and send the mixing control signals to the signal extraction device, where the mixing control signals are generated in a first temperature region, and the temperature of the first temperature region is higher than that of the second temperature region;

[0051] The signal extraction device includes: a first filtering and receiving device, an oscillator, and a first mixer;

[0052] The first filtering and receiving device is configured to filter the received mixing control signal and send the obtained filtered control signal to the first mixer;

[0053] The oscillator is configured to generate a local oscillator signal corresponding to the filtered control signal and send it to the first mixer;

[0054] The first mixer is configured to down-convert the received filtered control signal and the corresponding local oscillator signal to recover the control signal, and send the control signal to the quantum chip, where the control signal is used to manipulate the quantum bits in the quantum chip.

[0055] In the embodiment of the present application, the mixing control signal is transmitted through frequency division multiplexing technology, and down-converted in the low-temperature region so that the obtained control signal conforms to the operating frequency of the corresponding quantum bit, achieving the effect of manipulating the quantum bit. This method can reduce the number of signal transmission cables from the high-temperature region to the low-temperature region, reduce heat transfer caused by the cables, and also relieve the wiring problem on the quantum chip.

[0056] Combined with the third aspect, in the first possible implementation manner of the third aspect, the first coupling device is an antenna or a near-field coupling structure. Transmitting the mixing control signal through an antenna can reduce the number of transmission lines on the chip and more effectively solve the wiring problem; transmitting the mixing control signal through a near-field coupling structure has lower loss compared to the antenna method.

[0057] Combined with the first possible implementation manner of the third aspect, in the second possible implementation manner of the third aspect, the first coupling device is a first antenna, configured to broadcast the received mixing control signal; the first filtering and receiving device includes a first receiving antenna and a first filter, the first receiving antenna is configured to receive the mixing control signal and send the mixing control signal to the first filter; the first filter is configured to filter the mixing control signal and send the obtained filtered control signal to the first mixer.

[0058] Combined with the first possible implementation manner of the third aspect, in the third possible implementation manner of the third aspect, the first coupling device is a first antenna for broadcasting the received mixing control signal; the signal extraction device includes N first mixers, where N is an integer greater than 1; the first filtering and receiving device includes a third receiving antenna, a first power splitter, and N third filters. The third receiving antenna is used to receive the mixing control signal and send the mixing control signal to the first power splitter; the first power splitter is used to divide the mixing control signal into N paths and send them to the N third filters respectively; the third filter is used to filter one path of the received mixing control signal and send the obtained filtered control signal to the corresponding first mixer; each third filter is connected to a different first mixer.

[0059] Combined with the above possible implementation manners, in the fourth possible implementation manner of the third aspect, there are multiple first coupling devices, and the signals output by each first coupling device are used to control the qubits in different regions of the quantum chip.

[0060] Combined with the above possible implementation manners, in the fifth possible implementation manner of the third aspect, the signal extraction device further includes a signal filter for receiving the signal output by the first mixer, filtering out the high-frequency part of the output signal, and restoring the control signal, where the signal filter corresponds to the first mixer one by one.

[0061] Combined with the above possible implementation manners, in the sixth possible implementation manner of the third aspect, one first mixer corresponds to one qubit. Optionally, it is possible that one qubit requires multiple control signals, and in this case, it may correspond to multiple first mixers.

[0062] Combined with the above possible implementation manners, in the seventh possible implementation manner of the third aspect, the signal extraction device and the qubit are integrated on the same layer of the quantum chip; they can also be integrated on different layers of the quantum chip. When integrated on different layers, there is a shielding structure or shielding layer between the layer where the signal extraction device is located and the layer where the qubit is located, reducing the influence of interference signals on the qubit manipulation.

[0063] Combined with the above possible implementation manners, in the eighth possible implementation manner of the third aspect, the first mixer is an SIS mixer or an HEB mixer.

[0064] In the embodiments of the present application, the frequency division multiplexing technology is used to transmit the mixing control signal, and the mixing control signal is down-converted in the low-temperature region so that the obtained control signal conforms to the working frequency of the corresponding qubit, achieving the effect of manipulating the qubit. This method can reduce the number of signal transmission cables from the high-temperature region to the low-temperature region and reduce the heat transfer caused by the cables; moreover, through methods such as antenna broadcasting, the wiring problem on the quantum chip can be further alleviated to adapt to the further growth of the number of qubits in the future. Description of the Drawings

[0065] Figure 1 is a schematic structural diagram of a dilution refrigerator under normal circumstances;

[0066] Figure 2 is a schematic structural diagram of a qubit under normal circumstances;

[0067] Figure 3 is a qubit control signal generation device provided by the present application;

[0068] Figure 4 is another qubit control signal generation device provided by the present application;

[0069] Figure 5(a) is a schematic diagram of a qubit control device provided by an embodiment of the present application;

[0070] Figure 5(b) is a schematic diagram of a qubit control device provided by another embodiment of the present application;

[0071] Figure 5(c) is a schematic diagram of a qubit control device provided by another embodiment of the present application;

[0072] Figure 5(d) is a schematic diagram of a qubit control device provided by another embodiment of the present application;

[0073] Figure 6 is a schematic diagram of a filtering and receiving device provided by an embodiment of the present application;

[0074] Figure 7 is a schematic diagram of the planar layout of a quantum chip provided by an embodiment of the present application;

[0075] Figure 8 is a side view of a quantum chip provided by an embodiment of the present application;

[0076] Figure 9 is a side view of a quantum chip provided by another embodiment of the present application;

[0077] Figure 10 is a schematic diagram of a qubit control device provided by another embodiment of the present application;

[0078] Figure 11 is a schematic diagram of a filtering and receiving device provided by another embodiment of the present application;

[0079] Figure 12 Schematic diagram of the planar layout of a quantum chip provided in another embodiment of the present application;

[0080] Figure 13 Schematic diagram of the planar layout of a quantum chip provided in another embodiment of the present application;

[0081] Figure 14 Schematic diagram of a quantum bit control device provided in another embodiment of the present application;

[0082] Figure 15 Schematic diagram of a quantum bit control device provided in another embodiment of the present application;

[0083] Figure 16 Flowchart of a quantum bit control method provided in an embodiment of the present application;

[0084] Figure 17 Flowchart of a method for generating a quantum bit control signal provided in an embodiment of the present application. Detailed implementation manners

[0085] Next, the technical solutions in the embodiments of the present application will be described in conjunction with the accompanying drawings in the embodiments of the present application.

[0086] The present application provides a quantum bit control signal generation device 300, as Figure 3 shown, including: a control signal generator 301, a local oscillator signal generator 302, a second mixer 303, and a combiner 304 located in the first temperature zone, and a quantum chip located in the second temperature zone, wherein the temperature of the first temperature zone is higher than that of the second temperature zone. Usually, the temperature of the first temperature zone can be room temperature, the temperature of the second temperature zone can be lower than 4K or around 4K, and the lowest temperature of the first temperature zone is also higher than the highest temperature of the second temperature zone; it should be understood that the temperature zones described in the present application are all a temperature range. It should be noted that since the size of future superconducting quantum chips can be made smaller, the frequency of the control signals required for their manipulation signals will be further increased, which will enable them to work in an environment with a higher temperature. Therefore, the working temperature of future quantum chips may be increased to 100mK or even higher, and the working temperature of the quantum chips in the embodiments of the present application is not limited.

[0087] The control signal generator 301 and the local oscillator signal generator 302 are respectively connected to the second mixer 303. Among them, one control signal and one local oscillator signal form a group, and there are at least two groups. The sum of the frequencies of the control signal and the local oscillator signal in each group is different; the second mixer 303 is used to perform up-conversion on the control signal and the local oscillator signal in each group to obtain multiple mixing control signals with different frequencies; the combiner 304 is used to receive the mixing control signals, combine the multiple mixing control signals into one path, and send them to the quantum chip 305 through the first transmission medium. Among them, the mixing control signal is used to manipulate the qubits in the quantum chip 305.

[0088] In the embodiment of the present application, the conventional control signal is up-converted to a higher frequency band, and the control signals corresponding to different qubits are up-converted to different frequency bands to achieve differentiation in frequency. Thus, frequency division multiplexing technology can be used to reduce the number of signal cables, reduce heat transfer caused by the cables, and also relieve the wiring problem on the quantum chip.

[0089] Under normal circumstances, the control signals corresponding to superconducting qubits are all in the low-frequency band (usually 4 - 8 GHz, or can be between zero frequency and 2 GHz, and the frequency may change with technological progress), and the frequencies are relatively close. In order to achieve differentiation in frequency, it is necessary to use the local oscillator signal to perform up-conversion with the control signal to up-convert different control signals to different frequency bands to obtain mixing control signals. There are usually two ways to generate the mixing control signals:

[0090] (1) Generate local oscillator signals with different frequencies, and the frequencies of the local oscillator signals are separated by a sufficient distance; the frequencies of the control signals corresponding to different qubits can be the same or similar. One local oscillator signal corresponds to one control signal, and the control signals corresponding to different local oscillator signals are respectively up-converted with the corresponding local oscillator signals. The up-converted control signals do not overlap with each other and are in a completely distinguishable state. At this time, the up-converted control signals on each path can be combined into one signal through the combiner and sent out. In addition, the local oscillator signals with different frequencies can also be combined into one signal and sent out; the specific structure can be as Figure 3 shown.

[0091] (2) Generate control signals with different frequencies, and each control signal corresponds to one qubit; at this time, one local oscillator signal can be used to perform up-conversion on the control signals with different frequencies, and the up-converted control signals are in a completely distinguishable state. At this time, the up-converted control signals on each path can be combined into one signal through the combiner and sent out. The local oscillator signal can be sent out directly, and the specific structure can be as Figure 4 shown.

[0092] It should be noted that there are many other ways to generate the mixing control signal. For example, some local oscillator signals have the same frequency, and the local oscillator signals with the same frequency correspond to different frequency control signals. Taking three control signals and three local oscillator signals as an example, assume that the frequencies of local oscillator signals 1 and 2 are the same, both f1, and the frequency of local oscillator signal 3 is f2; the frequency of control signal 1 is f3, and the frequencies of control signals 2 - 3 are f4; as long as the frequencies after up-conversion of local oscillator signal 1 and control signal 1, f1 + f3, the frequencies after up-conversion of local oscillator signal 2 and control signal 2, f1 + f4, and the frequencies after up-conversion of local oscillator signal 3 and control signal 3, f2 + f4, are different from each other and can be distinguished. The above is just an example, and the present application does not limit the specific method.

[0093] In addition, considering that the mixing control signal also needs to be down-converted in the second temperature zone, as long as the mixing control signals with different frequencies can be distinguished and the frequency difference between the corresponding local oscillator signal and it meets the operating frequency of the qubit, the requirements can be met. Then, the frequency interval between the local oscillator signals used for up-conversion only needs to be greater than the bandwidth of the control signal. Since there is only a bandwidth of 8 - 16 GHz between the image frequency and the signal frequency of a control signal (for example, if the designed qubit frequency is 5 GHz, then there is a 10 GHz bandwidth), the entire frequency spectrum space needs to be divided into multiple intervals. Each interval contains a space of 12 - 24 GHz and can accommodate approximately (4 - 8 GHz) / 500 MHz = 8 - 16 signal passbands. Within a bandwidth of 20 - 70 GHz, about 100 signal passbands can be accommodated.

[0094] Furthermore, if multiple-frequency local oscillator signals are used to generate the mixing control signal, similar to the above method (1), these local oscillator signals with different frequencies can be combined into one path and sent out through the second transmission medium. At this time, they can share the same combiner with the mixing control signal (as long as the ports are sufficient), or another combiner can be used for combining; if one local oscillator signal is used to perform up-conversion with control signals of different frequencies to generate the mixing control signal, similar to the above method (2), the local oscillator signal can be transmitted alone through the second transmission medium, or together with the mixing control signal through the first transmission medium. Among them, the first transmission medium can be a coaxial cable or a dielectric waveguide; the second transmission medium can also be a coaxial cable or a dielectric waveguide, and this embodiment does not limit this.

[0095] In addition, at the end of the transmission medium (the first transmission medium and / or the second transmission medium), the signal can enter the quantum chip in three ways. One is to directly connect the transmission medium to the chip, or connect to the quantum chip after passing through a PCB (or an adapter board made of other materials). The second way is that the end of the transmission medium is not directly connected to any object, but is coupled to the quantum chip by near-field coupling, or is coupled to a PCB (or an adapter board made of other materials) by near-field coupling and then connected to the chip. The third way is that the end of the transmission medium forms a small-scale broadcast, broadcasting the mixing control signals and local oscillator signal lights of different frequencies to the quantum chip. Different bits on the quantum chip correspond to a different receiving device to receive control signals of different frequencies.

[0096] Another embodiment of the present application provides a quantum bit control device, including: a first coupling device, a second coupling device, at least one signal extraction device, and a quantum chip located in the second temperature zone; wherein, the first coupling device is configured to receive a plurality of mixing control signals from the first transmission medium and send the mixing control signals to the signal extraction device, wherein the frequencies of each mixing control signal are different; the second coupling device is configured to receive a local oscillator signal from the second transmission medium and send the local oscillator signal to the signal extraction device, wherein the mixing control signals and the local oscillator signal are generated in the first temperature zone, and the temperature of the first temperature zone is higher than that of the second temperature zone.

[0097] The signal extraction device includes: a first filtering and receiving device, a second filtering and receiving device, and a first mixer; the first filtering and receiving device is configured to filter the received mixing control signals and send the obtained filtered control signals to the first mixer; the second filtering and receiving device is configured to filter the received local oscillator signals and send the obtained filtered local oscillator signals to the first mixer; the first mixer is configured to perform down-conversion on the filtered control signals and the filtered local oscillator signals to recover the control signals and send the control signals to the quantum chip, wherein the control signals are used to manipulate the quantum bits in the quantum chip.

[0098] In the embodiment of the present application, the mixing control signals are transmitted by frequency division multiplexing technology, and down-conversion is performed on the mixing control signals in the low-temperature zone so that the obtained control signals conform to the working frequencies of the corresponding quantum bits, achieving the effect of manipulating the quantum bits. This method can reduce the number of signal transmission cables from the high-temperature zone to the low-temperature zone, reduce heat transfer caused by the cables, and also alleviate the wiring problem on the quantum chip.

[0099] Specifically, the first coupling device can be an antenna or a near-field coupling structure; the second coupling device can also be an antenna or a near-field coupling structure. Based on this, the present application provides a variety of specific structures to transmit signals to the quantum chip, such as Figure 5(a)-5(d)As shown, the qubit control device 500 further includes a first transmitting antenna 510, a second transmitting antenna 520, and at least one signal extraction device 530 located in the second temperature zone. Among them, the first transmitting antenna 510 is used to broadcast the mixing control signal received from the first transmission medium; the second transmitting antenna 520 is used to broadcast the local oscillator signal received from the second transmission medium; the signal extraction device 530 is used to extract the corresponding mixing control signal and local oscillator signal, perform down-conversion, and recover the control signal to manipulate the corresponding qubit.

[0100] Specifically, the signal extraction device 530 may include: a first filtering and receiving device 531, a second filtering and receiving device 532, and a first mixer 533; the first filtering and receiving device 531 is used to filter the received mixing control signal and send the obtained filtered control signal to the first mixer 533; the second filtering and receiving device 532 is used to filter the received local oscillator signal and send the obtained filtered local oscillator signal to the first mixer 533; and the first mixer 533 is used to perform down-conversion on the received filtered control signal and filtered local oscillator signal to recover the control signal.

[0101] It should be understood that each first mixer corresponds to a qubit, and the frequency of the control signal output by the first mixer conforms to the operating frequency of the corresponding qubit. Therefore, the signal frequencies output from the two filtering and receiving devices connected thereto to the first mixer are all preset. Among them, there are various specific implementation methods for the filtering and receiving device. For example, a horn antenna, a microstrip antenna, a waveguide slot antenna, etc. can be used. Through design, it can be made such that the filtering and receiving device only receives the mixing control signal or local oscillator signal of a specific frequency; or, a wider-spectrum receiving antenna can be selected, and at least one filter is added behind it. The passband of each filter corresponds to a special frequency point and bandwidth; therefore, there are various possibilities for the specific structure of the filtering and receiving device and its connection relationship with the first mixer, as shown below:

[0102] (1) The connection relationships between the first filtering and receiving device 531 and the second filtering and receiving device 532 and the first mixer 533 are shown in FIG. 5(a). The first filtering and receiving device 531 includes a first receiving antenna 5311 and a first filter 5312. Among them, the first receiving antenna 5311 is used to receive the mixing control signal, send the received mixing control signal to the first filter 5312, filter the mixing control signal through the first filter 5312, and send the obtained filtered control signal to the first mixer 533.

[0103] The second filtering receiving device 532 includes a second receiving antenna 5321 and a second filter 5322. Their connection relationship with the first mixer 533 is also shown in Fig. 5(a). Among them, the second receiving antenna 5321 is used to receive the local oscillator signal, send the local oscillator signal to the second filter, filter the local oscillator signal through the second filter 5322, and send the obtained filtered local oscillator signal to the first mixer 533.

[0104] (2) The connection relationships between the first filtering receiving device 531 and the second filtering receiving device 532 and the first mixer 533 are shown in Fig. 5(b). The first filtering receiving device 531 includes a third receiving antenna 5313, a first power splitter 5314, and N third filters 5315. Among them, the third receiving antenna 5313 is used to receive the mixing control signal, send the received mixing control signal to the first power splitter 5314, divide the mixing control signal into N paths through the first power splitter 5314, and then send the N paths of mixing control signals to the N third filters 5315 respectively; the third filter 5315 is used to filter one path of the received mixing control signal and send the obtained filtered control signal to the corresponding first mixer 533; in this case, each third filter 5315 is connected to a different first mixer 533, that is, the signal extraction device 530 includes N first mixers 533, where N is an integer greater than 1.

[0105] The second filtering receiving device 532 includes a fourth receiving antenna 5323, a second power splitter 5324, and N fourth filters 5325. Among them, the fourth receiving antenna 5323 is used to receive the local oscillator signal, send the local oscillator signal to the second power splitter 5324, divide the local oscillator signal into N paths through the second power splitter 5324, and then send them to the N fourth filters 5325 respectively; the fourth filter 5325 is used to filter one path of the received local oscillator signal and send the obtained filtered control signal to the corresponding first mixer 533; in this case, each fourth filter 5325 is also connected to a different first mixer 533.

[0106] (3) The connection relationships between the first filtering receiving device 531 and the second filtering receiving device 532 and the first mixer 533 are shown in Fig. 5(c). The first filtering receiving device 531 includes a first receiving antenna 5311 and a first filter 5312. Among them, the first receiving antenna 5311 is used to receive the mixing control signal, send the received mixing control signal to the first filter 5312, filter the mixing control signal through the first filter 5312, and send the obtained filtered control signal to the corresponding first mixer 533.

[0107] The second filtering and receiving device 532 includes a fourth receiving antenna 5323, a second power splitter 5324, and N fourth filters 5325. Among them, the fourth receiving antenna 5323 is used to receive a local oscillator signal, send the local oscillator signal to the second power splitter 5324, divide the local oscillator signal into N paths through the second power splitter 5324, and then send them to the N fourth filters 5325 respectively; the fourth filter 5325 is used to filter a received local oscillator signal path and send the obtained filtered local oscillator signal to the corresponding first mixer 533; in this case, each fourth filter 5325 is connected to a different first mixer 533, and the signal extraction device 530 includes N first filtering and receiving devices 531 and N first mixers 533. Each first mixer 533 down-converts the corresponding filtered control signal and filtered local oscillator signal to recover the control signal for manipulating the corresponding qubit on the quantum chip, where N is an integer greater than 1.

[0108] (4) The connection relationships between the first filtering and receiving device 531 and the second filtering and receiving device 532 and the first mixer 533 are shown in Fig. 5(d). The first filtering and receiving device 531 includes a third receiving antenna 5313, a first power splitter 5314, and N third filters 5315. Among them, the third receiving antenna 5313 is used to receive a mixing control signal, send the received mixing control signal to the first power splitter 5314, divide the mixing control signal into N paths through the first power splitter 5314, and then send the N paths of mixing control signals to the N third filters 5315 respectively; the third filter 5315 is used to filter a received mixing control signal path and send the obtained filtered control signal to the corresponding first mixer 533; in this case, each third filter 5315 is connected to a different first mixer 533, that is, the signal extraction device 530 includes N first mixers 533, where N is an integer greater than 1.

[0109] The second filtering and receiving device 532 includes a second receiving antenna 5321 and a second filter 5322, and its connection relationship with the first mixer 533 is also shown in Fig. 5(a). Among them, the second receiving antenna 5321 is used to receive a local oscillator signal, send the local oscillator signal to the second filter, filter the local oscillator signal through the second filter 5322, and send the obtained filtered local oscillator signal to the first mixer 533. At this time, the signal extraction device 530 further includes N second filtering and receiving devices 532, which correspond to the N first mixers 533 one by one.

[0110] It should be understood that the qubits in FIGS. 5(a)-(d) are only examples. The control signal can not only be transmitted to the qubits for manipulation, but also be transmitted to a control structure, for example, to an adjustable coupling structure, and the qubits can be manipulated through the adjustable coupling structure. In addition, a qubit may require one control signal for manipulation, or may require multiple control signals. If multiple control signals are required for manipulation, the qubit will correspond to multiple first mixers. The qubit control device of this embodiment can be simply modified, and the embodiments of the present application will not be elaborated further.

[0111] It should be noted that if a single local oscillator signal is used for upconversion, there is only one frequency for the local oscillator signal broadcast by the second transmitting antenna. In the above method, the second filtering and receiving device 532 may not include the second filter 5322, and the second antenna 5321 can be directly used for reception; however, adding the second filter 5322 can filter out stray waves or noise signals in other frequency bands, and further improve the performance. It should be understood that if the first filtering and receiving device is a designed narrowband receiving antenna, its connection relationship with the first mixer is also as shown in FIGS. 5(a) and (c), and it is directly connected to the corresponding first mixer.

[0112] In the above several methods, both the third receiving antenna 5313 and the fourth receiving antenna 5323 are wide-spectrum receivers. The passband of each filter corresponds to a special frequency point and bandwidth, and the corresponding control signal and local oscillator signal are selected for downconversion to recover the control signal for manipulating the qubits. At this time, the structure of the first filtering and receiving device 531 including the third receiving antenna 5313 can also be as Figure 6 shown. The output of the third receiving antenna 5313 enters a transmission medium (such as a waveguide, a microstrip transmission line, a coplanar waveguide transmission line, etc.). Different frequency-band filters are added at different positions of the transmission medium, and the filter can couple out the signal of its corresponding frequency band from the transmission medium and output it to the corresponding first mixer. Similarly, the second filtering and receiving device 532 including the fourth receiving antenna 5323 can also be of the structure as Figure 6 shown.

[0113] In addition, the connection relationship between the two filtering receiving devices provided by each of the above methods and the first mixer gives the structure of a signal extraction device, as shown in FIGS. 5(a)-(d). The qubit control device may include multiple signal extraction devices. The signal extraction device may be similar to that shown in FIG. 5(a), and each signal extraction device processes a pair of control signals and a local oscillator signal (referred to as signal extraction device 1); it may also be a structure similar to that shown in FIG. 5(b), where the signal extraction device corresponds to N pairs of control signals and local oscillator signals (referred to as signal extraction device 2); similarly, it may also be the structure of FIG. 5(c) or 5(d) (referred to as signal extraction device 3 or signal extraction device 4), or any combination of several structures may exist, and the present application does not limit. As for the number of signal extraction devices, it depends on the number of qubits. For example, if there are 100 qubits and N is 10, the qubit control device may include 100 signal extraction devices 1, or 10 signal extraction devices 2, or 10 signal extraction devices 3, or 10 signal extraction devices 4. Or, it may also include 10 signal extraction devices 1, 2 signal extraction devices 2, 3 signal extraction devices 3, and 4 signal extraction devices 4. In summary, as long as a total of 100 control signals can be generated to control 100 qubits respectively. If one qubit requires two control signals, the qubit control device may include 200 signal extraction devices 1, or 20 signal extraction devices 2, or 20 signal extraction devices 3, or 20 signal extraction devices 4. Or, it may also include 20 signal extraction devices 1, 4 signal extraction devices 2, 6 signal extraction devices 3, and 8 signal extraction devices 4, and the present application does not make a limitation.

[0114] Optionally, there is also a signal filter 534 between the first mixer and the corresponding qubit, and the signal filter 534 corresponds one-to-one with the first mixer 533; the signal output by the first mixer 533 will first pass through the signal filter 534 to filter out the high-frequency part of the output signal and recover the control signal to control the corresponding qubit.

[0115] In addition, since the first mixer will output a double-frequency signal and a difference-frequency signal at the same time, for this double-frequency signal, it can be passed into an impedance to be absorbed and turned into heat. The double-frequency signal can also be output from the chip and absorbed by impedance in the high-temperature area to turn into heat, or radiated out at a suitable place and absorbed by the shielding system. There are various ways to separate the double-frequency signal and the difference-frequency signal. For example, filtering in different frequency bands, or using a combination of multiple mixers with local oscillator phase shift and 3dB coupling, etc., and the present application does not make a limitation.

[0116] In addition, the layout relationship between the signal extraction device and the quantum chip is mainly divided into two types. One is that the signal extraction device and the superconducting qubit are on the same chip, which is abbreviated as single-chip integration. The other is that the signal extraction device and the superconducting qubit are not on the same chip, which is abbreviated as multi-chip packaging. The main differences between the two are as follows: one is the difficulty of wiring, and the other is the influence of high-frequency signals.

[0117] In terms of the difficulty of wiring, if the single-chip integration method is adopted, there will be a problem of wiring crossover. The core is that the superconducting qubits will be two-dimensionally arranged for a long time, and the coupling structure between the qubits will divide the chip plane into independent regions, so that the control signal lines of the superconducting qubits in the middle must use the cross-line technology to reach near the superconducting qubits from the edge. In the method of this embodiment, since the signal transmission is spatial, only the signal extraction device (filtering and receiving device, first mixer, signal filter, etc.) needs to be made in the area adjacent to the qubit, and the wiring problem can be avoided. The layout structure of single-chip integration is as Figure 7 shown. Therefore, for both single-chip integration and multi-chip packaging, this embodiment can be realized.

[0118] In terms of the influence of high-frequency signals, due to the use of the frequency-division multiplexing transmission method, the first transmission medium transmits multiple mixing control signals of different frequencies, that is, it is necessary to accommodate multiple sub-bands, so there may be signals with very high frequencies. At this time, it may have a negative impact on the superconducting quantum chip, superconducting quantum qubits, etc. Considering this influence, the multi-chip packaging method may be better because an isolation layer or shielding structure can be made on the upper chip to reduce the influence of the radiation signal on the superconducting chip. The specific structure is as Figure 8 shown. Further, more-chip packaging can also be adopted, and the layer closest to the superconducting quantum qubit can be used as a shielding layer, as Figure 9 shown.

[0119] Another way to reduce the influence of multi-subcarriers on superconducting qubits is to complete the reception in different regions and then connect to specific positions through signal routing.

[0120] In addition, limited by the difficulty and cost of the upper-end equipment when the up-conversion accommodates more sub-carriers, the number of sub-carriers (the number of signals of different frequencies) that a certain cable can transmit has an upper limit. However, in principle, the number of qubits on the quantum chip is continuously expanding with technological progress. Therefore, a method of multi-region segmentation and coverage may be required. The broadcast signal transmitted by each transmitting antenna covers different regions of the quantum chip, and shielding measures can be taken between regions to avoid signal crosstalk.

[0121] Optionally, the first mixer can be an SIS mixer or an HEB mixer or other mixers that can work at low temperature.

[0122] Another embodiment of the present application further provides a qubit control device. The difference in its structure from the previous embodiment is that the spatial radiation is changed to near-field coupling or small-area radiation coupling. Correspondingly, the wiring structure and the like will be changed. Specifically, as Figure 10 shown, the qubit control device 1000 further includes a first near-field coupling structure 1010, a second near-field coupling structure 1020, and a signal extraction device 1030 located in the second temperature zone. The first near-field coupling structure 1010 is used to couple the mixed-frequency control signal received from the first transmission medium to the signal extraction device 1030. The second near-field coupling structure 1020 is used to couple the local oscillator signal received from the second transmission medium to the signal extraction device 1030. When using the near-field coupling method to receive the control signal and the local oscillator signal, a near-field coupling structure needs to be designed on the chip. The near-field coupling structure can be a directly designed dielectric waveguide-metal waveguide transition structure, or a coplanar waveguide probe can be designed on the chip and placed at the 1 / 4 wavelength position to make the coupling energy on the probe the strongest, realizing the dielectric waveguide-coplanar waveguide conversion. In addition, a lens structure can also be designed at the end face of the dielectric waveguide to increase the coupling efficiency.

[0123] The signal extraction device 1030 includes: a first filtering and receiving device 1031, a second filtering and receiving device 1032, and M first mixers 1033, as Figure 11 shown; the first filtering and receiving device 1031 is used to filter the received mixed-frequency control signal and send the obtained M filtered control signals to the corresponding first mixers 1033 respectively. Among them, the frequencies of each filtered control signal are different, and M is an integer greater than 1. The second filtering and receiving device 1032 is used to filter the received local oscillator signal and send the obtained M filtered local oscillator signals to the corresponding first mixers 1033. The first mixer 1033 down-converts the received filtered control signal and the filtered local oscillator signal to recover the control signal.

[0124] Further, the first filtering receiving device 1031 includes a third power divider 10311 and M fifth filters 10312. Among them, the third power divider 10311 is configured to divide the mixing control signal into M paths and send them to the M fifth filters 10312 respectively; and the fifth filter 10312 is configured to filter the received mixing control signal of one path and send the obtained filtered control signal to the corresponding first mixer 1033. The second filtering receiving device 1032 includes a fourth power divider 10321 and M sixth filters 10322. Among them, the fourth power divider 10321 is configured to divide the local oscillator signal into M paths and send them to the M sixth filters 10322 respectively; the sixth filter 10322 is configured to filter the received local oscillator signal of one path and send the obtained filtered local oscillator signal to the corresponding first mixer. In this embodiment, each fifth filter is connected to a different first mixer, and each sixth filter is connected to a different first mixer.

[0125] In addition, the structure of the first filtering receiving device 1031 can also be as Figure 6 shown. The output of the first near-field coupling structure 1010 enters a transmission medium (such as a waveguide, a microstrip transmission line, a coplanar waveguide transmission line, etc.). Filters with different frequency bands are added at different positions of the transmission medium. The filters can couple out the signals of their corresponding frequency bands from the transmission medium and output them to the corresponding first mixers. Similarly, the second filtering receiving device 1032 can also be a structure as Figure 6 shown.

[0126] Optionally, there is also a signal filter 1034 between the first mixer 1033 and the corresponding qubit. The signal filter 1034 has a one-to-one correspondence with the first mixer 1033; the signal output by the first mixer 1033 will first pass through the signal filter 1034 to filter out the high-frequency part of the output signal and recover the control signal to control the corresponding qubit.

[0127] This embodiment is the same as the previous embodiments in terms of generating and transmitting mixing control signals of different frequencies, and is also the same as the previous embodiments in terms of filters, first mixers, etc. The difference from the previous embodiments lies in the way of coupling signals onto the chip. This embodiment proposes to use the near-field coupling or small-area radiation coupling method. This method does not require the signal to cover a large area of the chip and multiple receiving devices thereon. It only needs to couple to one receiving device on the chip (if it is area-divided coupling, there may be multiple receiving devices). It can avoid the loss of signal power and minimize the influence of the radiation signal on the chip. In addition, a shielding structure can be added around the near-field coupling or small-area radiation coupling structure to further reduce the influence on other areas of the chip.

[0128] In this embodiment, since the signal is first coupled to a certain point on the chip, it is necessary to consider the wiring problem from this point to the vicinity of each qubit. If the signal extraction device, signal filter, etc. and the qubits are placed on the same chip, there will be a problem of cross-wiring; if the two are separated, that is, the qubits are on the same layer and other structures are placed on another layer, the control signal output by the first mixer is connected to the vicinity of the superconducting qubit through interlayer coupling (such as connected to the layer where the qubit is located through micro-bumps (bump) and vias, etc.), and at this time, the cross-wiring problem can be avoided. For the case of layering, reference can be made to the wiring method as shown in Figure 12 ; if the signal is coupled to the substrate, the signal is first introduced from the substrate onto the chip, and the wiring after being introduced onto the chip can still refer to Figure 12 .

[0129] If the areas of structural components such as filters and mixers cannot be reduced to the extent that they can be placed near the qubits, or for other considerations, these structures are at a certain distance from the quantum chip, then a more general wiring situation can be considered, such as shown in Figure 13 , where one transmission cable corresponds to one mixing chip. On the mixing chip, each mixing control signal is separated and down-converted to obtain K control signals, and then these control signals independently route to the corresponding qubits of the superconducting quantum chip. This wiring method has high feasibility. It should be understood that the mixing chip is just a name and may include all or part of the components of the signal extraction device in this application and can be a functional element composed of these devices, and it is not necessarily limited to a single chip. In addition, if the structure responsible for coupling the signal to the chip is not integrated on the quantum chip, a cable connector (such as SMA, SMP, etc.) can also be used to replace the near-field coupling structure to ensure the alignment of the mixing control signal and / or the local oscillator signal and improve the signal transmission quality.

[0130] It should be noted that whether the signal is transmitted by spatial radiation or near-field coupling, it is not required that both the control signal and the local oscillator signal must use the same method. It can also be that the control signal is transmitted by antenna broadcast and the local oscillator signal is transmitted through a near-field coupling structure, and vice versa. The structure for transmitting the signal by antenna broadcast can be referred to Figure 5(a)-5(d) , and the structure for transmitting the signal through a near-field coupling structure can be referred to Figure 10 . In addition, if it is divided into regions for coverage, the signal transmission methods used in each region are independent. For example, the control signal covering a certain region is transmitted by antenna broadcast, while the local oscillator signal is transmitted through a near-field coupling structure; for another region, both the control signal and the local oscillator signal may be transmitted by antenna broadcast; in this regard, this application does not impose any restrictions.

[0131] In another embodiment of the present application, the local oscillator signal for down-conversion can be generated in the second temperature zone, that is, there is no need to transmit the local oscillator signal from the first temperature zone to the second temperature zone through a transmission medium. At this time, the structure of the qubit control device is similar to that described in the previous embodiment, except that the device for receiving the local oscillator signal is replaced with an oscillator that directly generates the local oscillator signal. For example, the second transmitting antenna and the second filtering and receiving device in FIGS. 5(a)-(d) are replaced with an oscillator, or Figure 10 the second near-field coupling structure and the second filtering and receiving device in are replaced with an oscillator. Taking the transmission of control signals through transmitting antennas and receiving antennas as an example, its structure can be as Figure 14 shown. The qubit control device further includes a first transmitting antenna 1410 and at least one signal extraction device 1420 located in the second temperature zone; wherein, the first transmitting antenna 1410 is used to broadcast the mixing control signal received from the first transmission medium; and the signal extraction device 1420 may further include a first filtering and receiving device 1421, an oscillator 1422, and a first mixer 1423; the first filtering and receiving device 1421 is used to filter the received mixing control signal and send the obtained filtered control signal to the first mixer 1423; the oscillator 1422 is used to generate a local oscillator signal corresponding to the filtered control signal and also send it to the first mixer 1423; the two signals are down-converted through the first mixer 1423 to recover the control signal to manipulate the qubit.

[0132] Specifically, the oscillator located in the second temperature zone can be a superconducting tunnel junction SIS source. By adjusting the SIS source frequency with a DC signal, local oscillator signals of different frequencies are generated. Since the SIS source tuning step is large (on the order of dozens of MHz), while quantum computing requires small-step tuning of the control signal, therefore, it is necessary to finely adjust the carrier frequency of the control signal on the normal temperature side to achieve KHz-level step control. Usually, a DC source is used to control the step of the oscillator.

[0133] Another embodiment of the present application further provides a qubit control device. Each control signal independently uses a dielectric waveguide to reduce crosstalk and is coupled to the quantum chip through a near-field coupling method. The local oscillator signal is a single-frequency signal and is radiated to the quantum chip through an antenna. Its structure is as Figure 15 shown. The qubit control device includes n control signal generators 1501, a local oscillator signal generator 1502, n near-field coupling structures 1503, n first mixers 1504, a transmitting antenna 1505, n receiving antennas 1506, and a quantum chip. Wherein, n is an integer greater than 1; the control signal generator 1501 and the local oscillator signal generator 1502 are located in the first temperature zone, and other components are located in the second temperature zone, and the temperature of the first temperature zone is higher than that of the second temperature zone.

[0134] Each control signal generator 1501 generates high-frequency control signals, which are respectively transmitted to the second temperature zone through a first transmission medium, and coupled to the first mixer 1504 through their corresponding near-field coupling structures 1503. Among them, the n control signal generators 1501, the n near-field coupling structures 1503, the n first mixers 1504, and the n receiving antennas 1506 are in one-to-one correspondence. The local oscillator signal generator 1502 generates a single-frequency local oscillator signal, which is transmitted to the second temperature zone through a second transmission medium, and then the local oscillator signal is broadcast through the transmitting antenna 1505; the n receiving antennas 1506 receive the broadcast local oscillator signal and send the received local oscillator signal to the corresponding first mixer 1504; the first mixer 1504 performs down-conversion on the received control signal and local oscillator signal to obtain a control signal that conforms to the working frequency of the qubits on the quantum chip, and uses it to manipulate the qubits.

[0135] Optionally, between the first mixer 1504 and the quantum chip, there is also a signal filter 1507, and the signal filter 1507 is in one-to-one correspondence with the first mixer 1504; the signal output by the first mixer 1504 will first pass through the signal filter 1507 to filter out the high-frequency part of the output signal, so as to better recover the control signal to manipulate the corresponding qubits. In addition, the part of the qubit control device located in the second temperature zone can be in a vacuum state to prevent heat transfer and interference from other signals to the manipulation of the qubits.

[0136] It should be noted that since the working frequency of the superconducting qubits is related to the manufacturing process, that is, the working frequency of each prepared qubit may have an error compared with the predetermined value, there are certain floating requirements for the filtering bandwidth of the signal filters, filtering receiving devices, etc. located in the second temperature zone. In addition, the filtering bandwidths of the filtering receiving devices corresponding to multiple control signals with different frequencies and subsequent signal filters and other devices can also be wider than the ideal value to facilitate adaptation to a certain error.

[0137] Another embodiment of the present application also provides a qubit control method, which is applied to the qubit control device disclosed in the present application, and the process is as Figure 16 shown, and the method includes:

[0138] 1601. Receive a plurality of mixed-frequency control signals from the first transmission medium in the second temperature zone.

[0139] 1602. Receive the local oscillator signal from the second transmission medium in the second temperature zone, where the mixed-frequency control signal and the local oscillator signal are generated in the first temperature zone, and the temperature of the first temperature zone is higher than that of the second temperature zone.

[0140] 1603. Filter the mixed-frequency control signal;

[0141] 1604. Filter the local oscillator signal;

[0142] 1605. Down-convert the filtered control signal and the filtered local oscillator signal to recover the control signal for manipulating the qubits in the quantum chip. Here, both the filtered control signal and the filtered local oscillator signal are multiple and correspond one by one.

[0143] In the embodiment of the present application, the mixed control signal is transmitted through the frequency division multiplexing technology, and the mixed control signal is down-converted in the low-temperature region so that the obtained control signal conforms to the working frequency of the corresponding qubit, achieving the effect of manipulating the qubit. This method can reduce the number of signal transmission cables from the high-temperature region to the low-temperature region, reduce the heat transfer caused by the cables, and also relieve the wiring problem on the quantum chip.

[0144] Optionally, after receiving multiple mixed signals from the first transmission medium, the method further includes: dividing the mixed control signal into N paths and filtering the N paths of mixed control signals respectively, where N is an integer greater than 1.

[0145] Optionally, after receiving the local oscillator signal from the second transmission medium, the method further includes: dividing the local oscillator signal into N paths and filtering the N paths of local oscillator signals respectively, where N is an integer greater than 1.

[0146] Optionally, the frequencies of the control signals in each group are different, and / or the frequencies of the local oscillator signals in each group are different. If multiple local oscillator signals with different frequencies are mixed with the control signal, the multiple local oscillator signals with different frequencies can also be combined into one path and sent out through the second transmission medium. The specific method of generating the mixed control signal has been described in detail in the device embodiment and will not be elaborated in this application.

[0147] Optionally, the first transmission medium can be a coaxial cable or a dielectric waveguide; the second transmission medium can also be a coaxial cable or a dielectric waveguide.

[0148] Furthermore, the local oscillator signal can also be generated in the second temperature region. In this case, there is no need to transmit the local oscillator signal. Optionally, after down-converting the filtered control signal and the filtered local oscillator signal, the signal obtained after down-conversion can be filtered first to filter out the high-frequency part of the signal, so as to better recover the control signal to manipulate the corresponding qubit.

[0149] In addition, if a designed horn antenna, microstrip antenna, waveguide slot antenna, etc. is adopted, it can only receive the mixing control signal or local oscillator signal of a specific frequency, which is equivalent to the antenna having a built-in filtering function; if a wider-spectrum receiving antenna is adopted, filtering is performed after reception; if the receiving bandwidth of the receiving antenna can include the frequencies of multiple mixing signals (or local oscillator signals), the received mixing control signal can be divided into multiple paths, and each path of the mixing control signal is filtered separately. For example, if the receiving antenna includes the frequencies of N mixing control signals, these N mixing control signals can be received, and these signals can be filtered out separately through the corresponding filters, where N is an integer greater than 1. The specific implementation method has been described in detail in the device embodiment, and will not be elaborated in the embodiment of the present application.

[0150] In addition, the control signal and / or local oscillator signal can be transmitted by means of broadcasting, and can also be transmitted by means of near-field coupling. For example, the mixing control signal and local oscillator signal are received through a near-field coupling structure, the received mixing control signal is divided into M paths, and each path of the mixing control signal is filtered separately; the received local oscillator signal is also divided into M paths, and each path of the local oscillator signal is filtered separately, where M is an integer greater than 1; then, the filtered control signal and the filtered local oscillator signal are down-converted to recover the control signal, where the M paths of filtered mixing control signals and the M paths of filtered local oscillator signals correspond one by one.

[0151] Furthermore, the present application also provides a method for generating a mixing control signal, the process is as Figure 17 shown, including:

[0152] 1701. Generate a control signal and a local oscillator signal in the first temperature zone, where one control signal and one local oscillator signal form a group, and there are at least two groups, and the sum of the frequencies of the control signal and the local oscillator signal in each group is different;

[0153] 1702. Up-convert the control signal and the local oscillator signal in each group to obtain multiple mixing control signals with different frequencies;

[0154] 1703. Synthesize the multiple mixing control signals into one path and send them to the quantum chip located in the second temperature zone through the first transmission medium, where the mixing control signal is used to manipulate the quantum bits in the quantum chip, and the temperature of the first temperature zone is higher than that of the second temperature zone.

[0155] Optionally, the frequencies of the control signals in each group are different, and / or the frequencies of the local oscillator signals in each group are different.

[0156] It should be understood that the "one embodiment" or "an embodiment" mentioned throughout the specification means that the specific features, structures or characteristics related to the embodiment are included in at least one embodiment of the present invention. Therefore, the "in one embodiment" or "in an embodiment" that appears throughout the specification does not necessarily refer to the same embodiment. In addition, these specific features, structures or characteristics can be combined in one or more embodiments in any suitable manner. In various embodiments of the present invention, the sequence numbers of the above processes do not mean the order of execution. The execution order of each process should be determined by its function and internal logic, and should not constitute any limitation to the implementation process of the embodiments of the present invention.

[0157] In several embodiments provided by the present application, it should be understood that the disclosed devices and methods can be implemented in other ways. For example, the device embodiments described above are merely illustrative. For example, the division of the units is only a logical function division. In actual implementation, there may be other division methods. For example, multiple units or components can be combined or integrated into another system, or some features can be ignored or not executed. In addition, the displayed or discussed coupling or direct coupling or communication connection between each other can be an indirect coupling or communication connection through some interfaces, devices or units, and can also be a connection in electrical or other forms.

[0158] In summary, the above is only a preferred embodiment of the technical solution of the present invention, and is not used to limit the protection scope of the present invention. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A quantum bit control device, characterized in that, the quantum bit control device includes a first coupling device, a second coupling device, at least one signal extraction device, and a quantum chip located in a second temperature zone; the first coupling device is configured to receive a plurality of mixing control signals from a first transmission medium and send the mixing control signals to the signal extraction device, wherein each mixing control signal has a different frequency; the second coupling device is configured to receive a local oscillator signal from a second transmission medium and send the local oscillator signal to the signal extraction device, wherein the mixing control signal and the local oscillator signal are generated in a first temperature zone, and the temperature of the first temperature zone is higher than that of the second temperature zone; the signal extraction device includes: a first filtering and receiving device, a second filtering and receiving device, and a first mixer; the first filtering and receiving device is configured to filter the received mixing control signal and send the obtained filtered control signal to the first mixer; the second filtering and receiving device is configured to filter the received local oscillator signal and send the obtained filtered local oscillator signal to the first mixer; the first mixer is configured to down-convert the filtered control signal and the filtered local oscillator signal to recover a control signal, and send the control signal to the quantum chip, wherein the control signal is used to manipulate the quantum bits in the quantum chip; the first coupling device is any one of an antenna, a near-field coupling structure, and a cable connector; the second coupling device is any one of an antenna, a near-field coupling structure, and a cable connector.

2. The quantum bit control device according to claim 1, characterized in that, the first coupling device is a first antenna configured to broadcast the received mixing control signals; the second coupling device is a second antenna configured to broadcast the received local oscillator signals; the first filtering and receiving device includes a first receiving antenna and a first filter; the first receiving antenna is configured to receive the mixing control signals and send the mixing control signals to the first filter; the first filter is configured to filter the mixing control signals and send the obtained filtered control signal to the first mixer; the second filtering and receiving device includes a second receiving antenna and a second filter; the second receiving antenna is configured to receive the local oscillator signals and send the local oscillator signals to the second filter; the second filter is configured to filter the local oscillator signals and send the obtained filtered local oscillator signal to the first mixer.

3. The quantum bit control device according to claim 1, characterized in that, the first coupling device is a first antenna configured to broadcast the received mixing control signals; the second coupling device is a second antenna configured to broadcast the received local oscillator signals; the signal extraction device includes N first mixers, where N is an integer greater than 1; The first filtering and receiving device includes a third receiving antenna, a first power divider, and N third filters. Among them, the third receiving antenna is configured to receive the mixing control signal and send the mixing control signal to the first power divider; the first power divider is configured to divide the mixing control signal into N paths and send them to the N third filters respectively; the third filter is configured to filter one path of the received mixing control signal and send the obtained filtered control signal to the corresponding first mixer; where each third filter is connected to a different first mixer. The second filtering and receiving device includes a fourth receiving antenna, a second power divider, and N fourth filters. Among them, the fourth receiving antenna is configured to receive the local oscillator signal and send the local oscillator signal to the second power divider; the second power divider is configured to divide the local oscillator signal into N paths and send them to the N fourth filters respectively; the fourth filter is configured to filter one path of the received local oscillator signal and send the obtained filtered local oscillator signal to the corresponding first mixer; where each fourth filter is connected to a different first mixer.

4. The quantum bit control device according to claim 1, characterized in that the first coupling device is a first antenna, configured to broadcast the received mixing control signal; the second coupling device is a second antenna, configured to broadcast the received local oscillator signal; the signal extraction device includes N first filtering and receiving devices and N first mixers, where N is an integer greater than 1; the first filtering and receiving device includes a first receiving antenna and a first filter. The first receiving antenna is configured to receive the mixing control signal and send the mixing control signal to the first filter; the first filter is configured to filter the mixing control signal and send the obtained filtered control signal to the corresponding first mixer; The second filtering and receiving device includes a fourth receiving antenna, a second power divider, and N fourth filters. Among them, the fourth receiving antenna is configured to receive the local oscillator signal and send the local oscillator signal to the second power divider; the second power divider is configured to divide the local oscillator signal into N paths and send them to the N fourth filters respectively; the fourth filter is configured to filter one path of the received local oscillator signal and send the obtained filtered local oscillator signal to the corresponding first mixer; where each fourth filter is connected to a different first mixer.

5. The quantum bit control device according to claim 1, characterized in that the first coupling device is a first antenna, configured to broadcast the received mixing control signal; the second coupling device is a second antenna, configured to broadcast the received local oscillator signal; the signal extraction device includes N second filtering and receiving devices and N first mixers, where N is an integer greater than 1; The first filtering and receiving device includes a third receiving antenna, a first power divider, and N third filters. Among them, the third receiving antenna is used to receive the mixing control signal and send the mixing control signal to the first power divider; the first power divider is used to divide the mixing control signal into N paths and send them to the N third filters respectively; the third filter is used to filter one path of the received mixing control signal and send the obtained filtered control signal to the corresponding first mixer; among them, each third filter is connected to a different first mixer; The second filtering and receiving device includes a second receiving antenna and a second filter. The second receiving antenna is used to receive the local oscillator signal and send the local oscillator signal to the second filter; the second filter is used to filter the local oscillator signal and send the obtained filtered local oscillator signal to the first mixer.

6. The quantum bit control device according to any one of claims 1-5, characterized in that, The first transmission medium is a coaxial cable or a dielectric waveguide; the second transmission medium is a coaxial cable or a dielectric waveguide.

7. The quantum bit control device according to claim 1, characterized in that, The first coupling device is a first near-field coupling structure or a first cable connector, and is used to couple the mixing control signal received from the first transmission medium to the signal extraction device; The second coupling device is a second near-field coupling structure or a second cable connector, and is used to couple the local oscillator signal received from the second transmission medium to the signal extraction device; The first filtering and receiving device is used to divide the received mixing control signal into M paths, filter them respectively, and send the obtained M filtered control signals to the corresponding first mixers respectively. Among them, the frequencies of each filtered control signal are different, and M is an integer greater than 1; The second filtering and receiving device is used to divide the received local oscillator signal into M paths, filter them respectively, and send the obtained M filtered local oscillator signals to the corresponding first mixers.

8. The quantum bit control device according to claim 7, characterized in that, The first filtering and receiving device includes a third power divider and M fifth filters. The third power divider is used to divide the mixing control signal into M paths and send them to the M fifth filters respectively; The fifth filter is used to filter one path of the received mixing control signal and send the obtained filtered control signal to the corresponding first mixer; among them, each fifth filter is connected to a different first mixer; The second filtering and receiving device includes a fourth power divider and M sixth filters. The fourth power divider is used to divide the local oscillator signal into M paths and send them to the M sixth filters respectively; the sixth filter is used to filter one path of the received local oscillator signal and send the obtained filtered local oscillator signal to the corresponding first mixer; among them, each sixth filter is connected to a different first mixer.

9. The quantum bit control device according to claim 1, It is characterized in that there are a plurality of the first coupling devices, and the signals output by each first coupling device are used to control the qubits in different regions of the quantum chip.

10. The qubit control device according to claim 1, it is characterized in that the signal extraction device further includes a signal filter, which is used to receive the signal output by the first mixer, filter out the high-frequency part of the output signal, and recover the control signal, wherein the signal filter corresponds to the first mixer one by one.

11. The qubit control device according to claim 1, it is characterized in that one first mixer corresponds to one qubit.

12. The qubit control device according to claim 1, it is characterized in that the signal extraction device and the qubit are integrated on the same layer of the quantum chip.

13. The qubit control device according to claim 1, it is characterized in that the signal extraction device and the qubit are integrated on different layers of the quantum chip.

14. The qubit control device according to claim 13, it is characterized in that there is a shielding structure or a shielding layer between the layer where the signal extraction device is located and the layer where the qubit is located.

15. The qubit control device according to claim 1, it is characterized in that the first mixer is a superconducting tunnel junction SIS mixer or a phonon-cooled superconducting HEB mixer.

16. The qubit control device according to claim 1, it is characterized in that the qubit control device further includes a control signal generator, a local oscillator signal generator, a second mixer and a combiner located in the first temperature zone; the control signal generator and the local oscillator signal generator are respectively connected to the second mixer, wherein one control signal and one local oscillator signal form a group, and there are at least two groups, and the sum of the frequencies of the control signal and the local oscillator signal in each group is different; the second mixer is used to perform up-conversion on the control signal and the local oscillator signal in each group to obtain a plurality of mixed control signals with different frequencies; the combiner is used to receive the mixed control signals, synthesize the plurality of mixed control signals into one path, and send them to the second coupling device through the first transmission medium, wherein the mixed control signals are used to manipulate the qubits in the quantum chip.

17. The qubit control device according to claim 16, it is characterized in that the frequencies of the control signals in each group are different, and / or the frequencies of the local oscillator signals in each group are different.

18. A qubit control method, it is characterized in that the method includes: receiving a plurality of mixed control signals from the first transmission medium through any one of an antenna, a near-field coupling structure and a cable connector in the second temperature zone; receiving a local oscillator signal from the second transmission medium through any one of an antenna, a near-field coupling structure and a cable connector in the second temperature zone, wherein the mixed control signal and the local oscillator signal are generated in the first temperature zone, and the temperature of the first temperature zone is higher than that of the second temperature zone; filtering the mixed control signal; filtering the local oscillator signal; The filtered control signal and the filtered local oscillator signal are down-converted to recover the control signal for manipulating the qubits in the quantum chip. Here, there are multiple filtered control signals and multiple filtered local oscillator signals, and they are in one-to-one correspondence.

19. The qubit control method according to claim 18, wherein, after receiving the multiple mixed control signals from the first transmission medium, the method further includes: dividing the mixed control signals into N paths, and filtering the N paths of the mixed control signals respectively, where N is an integer greater than 1.

20. The qubit control method according to claim 18 or 19, wherein, after receiving the local oscillator signal from the second transmission medium, the method further includes: dividing the local oscillator signal into N paths, and filtering the N paths of the local oscillator signals respectively, where N is an integer greater than 1.

21. The qubit control method according to claim 18, wherein, the first transmission medium is a coaxial cable or a dielectric waveguide; the second transmission medium is a coaxial cable or a dielectric waveguide.

22. The qubit control method according to claim 18, wherein, receiving the mixed control signal by means of broadcast radiation or near-field coupling; and / or receiving the local oscillator signal by means of broadcast radiation or near-field coupling.

23. The qubit control method according to claim 18, wherein, after down-converting the filtered control signal and the filtered local oscillator signal, the method further includes: filtering the signal after down-conversion to filter out the high-frequency part of the signal and recover the control signal.

24. The qubit control method according to claim 18, wherein, before receiving the mixed control signal and the local oscillator signal, the method further includes: generating a control signal and a local oscillator signal in a first temperature zone, where one control signal and one local oscillator signal form a group, and there are at least two groups, and the sum of the frequencies of the control signal and the local oscillator signal in each group is different; up-converting the control signal and the local oscillator signal in each group to obtain multiple mixed control signals with different frequencies; combining the multiple mixed control signals into one path and sending them to the quantum chip located in the second temperature zone through the first transmission medium.

25. The qubit control method according to claim 24, wherein, the frequencies of the control signals in each group are different, and / or the frequencies of the local oscillator signals in each group are different.

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