Quantum bit control method and device

Abstract

The invention discloses a quantum bit control method and device, and relates to the technical field of quantum. In the quantum bit control device, a control unit is used for controlling a trapping unit to trap a first quantum bit at a first position in a first optical resonant cavity and controlling the trapping unit to trap a second quantum bit at a second position in a second optical resonant cavity; the cavity lengths of the first optical resonant cavity and the second optical resonant cavity are set, so that the resonant frequency of the first optical resonant cavity comprises the mistuned red sideband transition frequency of the trapped first quantum bit, and the resonant frequency of the second optical resonant cavity comprises the mistuned blue sideband transition frequency of the trapped second quantum bit; and controlling the laser unit to input the laser of the resonant frequency of the first optical resonant cavity into the first optical resonant cavity, and controlling the laser unit to input the laser of the resonant frequency of the second optical resonant cavity into the second optical resonant cavity. The quantum gate control method and device can solve the problem that the implementation speed of the quantum gate is low, and are used for quantum bit control.

Description

Technical Field

[0001] This application relates to the field of quantum technologies, and particularly to a method and device for manipulating qubits. Background Art

[0002] During the process of quantum computing, a qubit manipulation device in a quantum computer needs to manipulate multiple qubits (qubits can be ions or atoms) in order to implement quantum logic gates (abbreviated as quantum gates).

[0003] Exemplarily, the qubit manipulation device includes a control unit, a trapping unit, and a laser unit. The control unit is used to control the trapping unit to trap multiple qubits. After that, the control unit can also control the laser unit to transmit lasers to the multiple qubits trapped by the trapping unit respectively to manipulate the multiple qubits. The manipulated multiple qubits are entangled with each other, which is beneficial to the implementation of quantum gates.

[0004] However, currently, the time required to manipulate multiple qubits is relatively long, resulting in a slow implementation speed of quantum gates. Summary of the Invention

[0005] This application provides a method and device for manipulating qubits, which can solve the problem of slow implementation speed of quantum gates. The solution provided by this application is as follows.

[0006] In a first aspect, this application provides a qubit manipulation device, which includes: a control unit, a trapping unit, a first optical resonator, a second optical resonator, and a laser unit.

[0007] The control unit is used to control the trapping unit to trap a first qubit at a first position in the first optical resonator, and control the trapping unit to trap a second qubit at a second position in the second optical resonator; after that, the control unit is used to set the cavity lengths of the first optical resonator and the second optical resonator so that the resonance frequency of the first optical resonator includes the detuned red sideband transition frequency of the trapped first qubit, and the resonance frequency of the second optical resonator includes the detuned blue sideband transition frequency of the trapped second qubit; finally, the control unit is used to control the laser unit to input a laser with the resonance frequency of the first optical resonator into the first optical resonator, and control the laser unit to input a laser with the resonance frequency of the second optical resonator into the second optical resonator. The above-mentioned first qubit and second qubit are both coupled to a target motion mode, and the motion direction of the target motion mode is not perpendicular to the cavity length directions of the first optical resonator and the second optical resonator;

[0008] According to the above content, the laser used to manipulate qubits in this application resonates in the optical resonator, thus amplifying the power of the laser. The amplification of the laser power can reduce the time required to manipulate multiple qubits and improve the implementation speed of quantum gates.

[0009] Optionally, after the laser unit inputs the laser with the resonance frequency of the first optical resonator into the first optical resonator, the first qubit is located at the antinode position of the laser resonating in the first optical resonator; after the laser unit inputs the laser with the resonance frequency of the second optical resonator into the second optical resonator, the second qubit is located at the antinode position of the laser resonating in the second optical resonator. It can be understood that after the control unit controls the laser unit to input the laser with the resonance frequency of the first optical resonator into the first optical resonator, the first qubit may not be located at the antinode position of the laser resonating in the first optical resonator. After the control unit controls the laser unit to input the laser with the resonance frequency of the second optical resonator into the second optical resonator, the second qubit may not be located at the antinode position of the laser resonating in the second optical resonator.

[0010] Optionally, after the control unit controls the laser unit to input the laser with the resonance frequency of the first optical resonator into the first optical resonator and controls the laser unit to input the laser with the resonance frequency of the second optical resonator into the second optical resonator, the control unit can also adjust the relationship between the qubit and the antinode position of the laser in the following manner to make the qubit located at the antinode position of the laser resonating in its corresponding optical resonator.

[0011] Exemplarily, the control unit is further configured to: when the first qubit is not located at the antinode position of the laser resonating in the first optical resonator, perform at least one first adjustment operation until the first qubit is located at the antinode position of the laser resonating in the first optical resonator; the first adjustment operation includes: controlling the trapping unit to adjust the first position, adjusting the cavity length of the first optical resonator according to the adjusted first position, and controlling the laser unit to input the laser with the resonance frequency of the first optical resonator with the adjusted cavity length into the first optical resonator;

[0012] The control unit is further configured to: when the second qubit is not located at the antinode position of the laser resonating in the second optical resonator, perform at least one second adjustment operation until the second qubit is located at the antinode position of the laser resonating in the second optical resonator; the second adjustment operation includes: controlling the trapping unit to adjust the second position, adjusting the cavity length of the second optical resonator according to the adjusted second position, and controlling the laser unit to input the laser with the resonance frequency of the second optical resonator with the adjusted cavity length into the second optical resonator.

[0013] It can be seen that after the control unit inputs laser into the optical resonator each time, it is necessary to detect whether the qubit in the optical resonator is located at the antinode position of the laser resonating in the optical resonator. If the qubit in the optical resonator is located at the antinode position of the laser resonating in the optical resonator, there is no need to change the position of the qubit, change the cavity length of the optical resonator, and change the frequency of the laser input into the optical resonator by the laser unit. If the qubit in the optical resonator is not at the antinode position of the laser resonating in the optical resonator, it is necessary to change the position of the qubit, change the cavity length of the optical resonator, and change the frequency of the laser input into the optical resonator by the laser unit.

[0014] When the qubit is located at the antinode position of the laser resonating in the optical resonator where it is located, the power amplification effect of the laser is better, and the error suppression effect on the quantum gate is better.

[0015] According to the foregoing introduction, during the process of the laser for manipulating the qubit resonating in the optical resonator, the laser changes from a traveling wave to a standing wave. Within the error range of the quantum gate, there is an upper limit to the reduction of the time required to manipulate multiple qubits by the traveling wave, while the reduction of the time required to manipulate multiple qubits by the standing wave can have no upper limit (such as when the qubit is located at the above-mentioned antinode position). Therefore, changing the laser for manipulating the qubit from a traveling wave to a standing wave helps to improve the implementation speed of the quantum gate.

[0016] Optionally, the qubit manipulation device further includes: a first displacement unit and a second displacement unit. The first displacement unit is connected to two reflectors in the first optical resonator, and the second displacement unit is connected to two reflectors in the second optical resonator; the control unit is configured to: control the first displacement unit to change the position of at least one reflector in the first optical resonator to set the cavity length of the first optical resonator; and control the second displacement unit to change the position of at least one reflector in the second optical resonator to set the cavity length of the second optical resonator. It can be understood that the qubit manipulation device may not include the first displacement unit and the second displacement unit. For example, the control unit is directly connected to two reflectors in the first optical resonator and to two reflectors in the second optical resonator and the second displacement unit. In this case, the control unit can directly set the cavity lengths of the first optical resonator and the second optical resonator.

[0017] The laser unit provided in this application includes a laser and a modulator. The laser is used to emit the laser to be modulated; the control unit is used to control the modulator to modulate the parameters (such as frequency) of the laser output by the laser, so as to obtain the laser that the laser unit needs to output. Optionally, in this application, the parameters of the laser output by the laser may further include at least one of amplitude and phase in addition to frequency. It can be seen that the modulator can perform pulse shaping on the laser output by the laser. For example, when the control unit needs to control the laser unit to output a laser sequence, the control unit is used to control the modulator to modulate the amplitude and phase of the laser output by the laser. Optionally, the laser sequence output by the control unit controlling the laser unit can be used to reduce the error of the quantum gate.

[0018] In the above embodiment, the quantum bit manipulation device includes the first optical resonator and the second optical resonator as an example. Optionally, the quantum bit manipulation device may further include more optical resonators. Optionally, the optical resonators in the quantum bit manipulation device may be arranged in an array, and correspondingly, the displacement units (such as the above-mentioned first displacement unit and second displacement unit) corresponding to each optical resonator may also be arranged in an array.

[0019] (1) In the first realizable manner of the optical resonator in the quantum bit manipulation device, the quantum bit manipulation device includes a plurality of first resonator groups. The first resonator group includes a first optical resonator and a second optical resonator; the detuned red sideband transition frequencies corresponding to the first optical resonators in different first resonator groups are different, and the detuned blue sideband transition frequencies corresponding to the second optical resonators in different first resonator groups are different.

[0020] In this way, the laser for manipulating the first quantum bit is power-enhanced in each first optical resonator, and the laser for manipulating the second quantum bit is power-enhanced in each second optical resonator. Moreover, the detuned red sideband transition frequencies corresponding to the first optical resonators in different first resonator groups are different, and the detuned blue sideband transition frequencies corresponding to the second optical resonators in different first resonator groups are different. For each first resonator group, the first quantum bit can undergo a detuned red sideband transition in the first optical resonator of the first resonator group, and the second quantum bit can undergo a detuned blue sideband transition in the second optical resonator of the first resonator group, achieving the effect of the first quantum bit and the second quantum bit undergoing carrier transitions. Under the action of multiple first resonator groups, the effect that the first quantum bit and the second quantum bit undergo multiple carrier transitions (the detuned red sideband transitions corresponding to different carrier transitions are different, and the detuned blue sideband transitions are also different) in multiple first resonator groups can be realized. The multiple carrier transitions can improve the robustness of quantum bit manipulation and reduce the error of quantum bit manipulation.

[0021] (2) In the second implementable manner of the optical resonator in the qubit manipulation device, the qubit manipulation device includes: a first resonator group and a second resonator group. The first resonator group includes a first optical resonator and a second optical resonator, and the second resonator group includes a third optical resonator and a fourth optical resonator; a first position is located within the third optical resonator, and a second position is located within the fourth optical resonator; the movement direction of the target movement mode is not perpendicular to the cavity length directions of both the third optical resonator and the fourth optical resonator; the control unit is further configured to: set the cavity lengths of the third optical resonator and the fourth optical resonator such that the resonance frequency of the third optical resonator includes the carrier transition frequency of the trapped first qubit, and the resonance frequency of the fourth optical resonator includes the carrier transition frequency of the trapped second qubit; and control the laser unit to input laser light with the resonance frequency of the third optical resonator into the third optical resonator, and control the laser unit to input laser light with the resonance frequency of the fourth optical resonator into the fourth optical resonator.

[0022] In this way, compared with the first implementable manner described above, not only can the effect of the carrier transition of the first qubit and the second qubit be achieved by the way that the first qubit undergoes a detuned red sideband transition and the second qubit undergoes a detuned blue sideband transition. Moreover, the effect of the carrier transition of the first qubit and the second qubit can also be achieved by the way that the first qubit and the second qubit undergo a carrier transition. In this way, the robustness of qubit manipulation can also be improved, and the error of qubit manipulation can be reduced.

[0023] Optionally, among the multiple resonator groups in the qubit manipulation device, at least two resonator groups share at least one optical resonator. In other words, the at least one optical resonator serves as an optical resonator in one resonator group among the at least two resonator groups and also serves as an optical resonator in other resonator groups. In this way, the number of optical resonators in the qubit manipulation device can be reduced, and the structural complexity of the qubit manipulation device can be lowered.

[0024] In a second aspect, the present application provides a quantum computer, including the qubit manipulation device according to any one of the designs in the first aspect, and a first qubit and a second qubit.

[0025] In a third aspect, a method for manipulating qubits is provided. The method is executed by a control unit in a qubit manipulation device, and the qubit manipulation device further includes: a trapping unit, a first optical resonator, a second optical resonator, and a laser unit. The method for manipulating qubits includes: the control unit first controls the trapping unit to trap a first qubit at a first position in the first optical resonator and controls the trapping unit to trap a second qubit at a second position in the second optical resonator; thereafter, the control unit sets the cavity lengths of the first optical resonator and the second optical resonator so that the resonance frequency of the first optical resonator includes the detuned red sideband transition frequency of the trapped first qubit and the resonance frequency of the second optical resonator includes the detuned blue sideband transition frequency of the trapped second qubit; finally, the control unit controls the laser unit to input laser light with the resonance frequency of the first optical resonator into the first optical resonator and controls the laser unit to input laser light with the resonance frequency of the second optical resonator into the second optical resonator. Both the first qubit and the second qubit are coupled to a target motion mode, and the motion direction of the target motion mode is not perpendicular to the cavity length directions of the first optical resonator and the second optical resonator.

[0026] Optionally, after the control unit controls the laser unit to input laser light with the resonance frequency of the first optical resonator into the first optical resonator, the first qubit is at the antinode position of the laser resonating in the first optical resonator; after the control unit controls the laser unit to input laser light with the resonance frequency of the second optical resonator into the second optical resonator, the second qubit is at the antinode position of the laser resonating in the second optical resonator.

[0027] Optionally, after the control unit controls the laser unit to input laser light with the resonance frequency of the first optical resonator into the first optical resonator and controls the laser unit to input laser light with the resonance frequency of the second optical resonator into the second optical resonator, the method further includes: when the first qubit is not at the antinode position of the laser resonating in the first optical resonator, the control unit performs at least one first adjustment operation until the first qubit is at the antinode position of the laser resonating in the first optical resonator; the first adjustment operation includes: controlling the trapping unit to adjust the first position, adjusting the cavity length of the first optical resonator according to the adjusted first position, and controlling the laser unit to input laser light with the resonance frequency of the first optical resonator after adjusting the cavity length into the first optical resonator; and when the second qubit is not at the antinode position of the laser resonating in the second optical resonator, the control unit performs at least one second adjustment operation until the second qubit is at the antinode position of the laser resonating in the second optical resonator; the second adjustment operation includes: controlling the trapping unit to adjust the second position, adjusting the cavity length of the second optical resonator according to the adjusted second position, and controlling the laser unit to input laser light with the resonance frequency of the second optical resonator after adjusting the cavity length into the second optical resonator;

[0028] Optionally, the qubit manipulation device further includes: a first displacement unit and a second displacement unit. The first displacement unit is connected to two mirrors in the first optical resonator, and the second displacement unit is connected to two mirrors in the second optical resonator. When setting the cavity lengths of the first optical resonator and the second optical resonator, the control unit can control the first displacement unit to change the position of at least one mirror in the first optical resonator to set the cavity length of the first optical resonator, and control the second displacement unit to change the position of at least one mirror in the second optical resonator to set the cavity length of the second optical resonator.

[0029] Optionally, the qubit manipulation device includes a plurality of first resonator groups; each first resonator group includes a first optical resonator and a second optical resonator; the detuned red sideband transition frequencies corresponding to the first optical resonators in different first resonator groups are different, and the detuned blue sideband transition frequencies corresponding to the second optical resonators in different first resonator groups are different.

[0030] Optionally, the qubit manipulation device includes: a first resonator group and a second resonator group. The first resonator group includes a first optical resonator and a second optical resonator, and the second resonator group includes a third optical resonator and a fourth optical resonator; a first position is located in the third optical resonator, and a second position is located in the fourth optical resonator; the movement direction of the target movement mode is not perpendicular to the cavity length directions of the third optical resonator and the fourth optical resonator; the qubit manipulation method further includes: the control unit sets the cavity lengths of the third optical resonator and the fourth optical resonator so that the resonance frequency of the third optical resonator includes the carrier transition frequency of the trapped first qubit, and the resonance frequency of the fourth optical resonator includes the carrier transition frequency of the trapped second qubit; and, the control unit controls the laser unit to input laser with the resonance frequency of the third optical resonator into the third optical resonator, and controls the laser unit to input laser with the resonance frequency of the fourth optical resonator into the fourth optical resonator.

[0031] Optionally, at least two resonator groups share at least one optical resonator.

[0032] Optionally, the laser unit includes: a laser and a modulator; the control unit is used to control the modulator to modulate multiple parameters of the laser output by the laser, the multiple parameters include frequency, and the multiple parameters further include at least one of amplitude and phase.

[0033] Fourthly, the present application provides a control unit, which includes: a first control module, a first setting module, and a second control module. The first control module is used to control the trapping unit to trap the first qubit at a first position in the first optical resonator, and control the trapping unit to trap the second qubit at a second position in the second optical resonator; both the first qubit and the second qubit are coupled to the target motion mode, and the motion direction of the target motion mode is not perpendicular to the cavity length directions of the first optical resonator and the second optical resonator.

[0034] The first setting module is used to set the cavity lengths of the first optical resonator and the second optical resonator, so that the resonance frequency of the first optical resonator includes the detuned red sideband transition frequency of the trapped first qubit, and the resonance frequency of the second optical resonator includes the detuned blue sideband transition frequency of the trapped second qubit.

[0035] The second control module is used to control the laser unit to input laser with the resonance frequency of the first optical resonator into the first optical resonator, and control the laser unit to input laser with the resonance frequency of the second optical resonator into the second optical resonator.

[0036] Optionally, after the second control module controls the laser unit to input laser with the resonance frequency of the first optical resonator into the first optical resonator, the first qubit is at the antinode position of the laser resonating in the first optical resonator.

[0037] After the second control module controls the laser unit to input laser with the resonance frequency of the second optical resonator into the second optical resonator, the second qubit is at the antinode position of the laser resonating in the second optical resonator.

[0038] Optionally, the control unit further includes:

[0039] A first adjustment module, which is used to perform at least one first adjustment operation until the first qubit is at the antinode position of the laser resonating in the first optical resonator when the first qubit is not at the antinode position of the laser resonating in the first optical resonator; the first adjustment operation includes: controlling the trapping unit to adjust the first position, adjusting the cavity length of the first optical resonator according to the adjusted first position, and controlling the laser unit to input laser with the resonance frequency of the first optical resonator after adjusting the cavity length into the first optical resonator.

[0040] A second adjustment module, configured to perform at least one second adjustment operation until the second qubit is at the antinode position of the laser resonating in the second optical resonator when the second qubit is not at the antinode position of the laser resonating in the second optical resonator; the second adjustment operation includes: controlling the trapping unit to adjust the second position, adjusting the cavity length of the second optical resonator according to the adjusted second position, and controlling the laser unit to input into the second optical resonator a laser with the resonance frequency of the second optical resonator after adjusting the cavity length;

[0041] Optionally, the qubit manipulation device further includes: a first displacement unit and a second displacement unit, the first displacement unit is connected to two reflectors in the first optical resonator, and the second displacement unit is connected to two reflectors in the second optical resonator; a first setting module is configured to control the first displacement unit to change the position of at least one reflector in the first optical resonator to set the cavity length of the first optical resonator; and control the second displacement unit to change the position of at least one reflector in the second optical resonator to set the cavity length of the second optical resonator.

[0042] Optionally, the qubit manipulation device includes a plurality of first resonator groups; each first resonator group includes a first optical resonator and a second optical resonator; the detuned red sideband transition frequencies corresponding to the first optical resonators in different first resonator groups are different, and the detuned blue sideband transition frequencies corresponding to the second optical resonators in different first resonator groups are different.

[0043] Optionally, the qubit manipulation device includes: a first resonator group and a second resonator group, the first resonator group includes a first optical resonator and a second optical resonator, and the second resonator group includes a third optical resonator and a fourth optical resonator; the first position is inside the third optical resonator, and the second position is inside the fourth optical resonator; the moving direction of the target motion mode is not perpendicular to the cavity length directions of both the third optical resonator and the fourth optical resonator; the control unit may further include a second setting module and a third control module. The second setting module is configured to set the cavity lengths of the third optical resonator and the fourth optical resonator so that the resonance frequency of the third optical resonator includes the carrier transition frequency of the trapped first qubit, and the resonance frequency of the fourth optical resonator includes the carrier transition frequency of the trapped second qubit; the third control module is configured to control the laser unit to input into the third optical resonator a laser with the resonance frequency of the third optical resonator, and control the laser unit to input into the fourth optical resonator a laser with the resonance frequency of the fourth optical resonator.

[0044] Optionally, at least two resonator groups share at least one optical resonator.

[0045] Optionally, the laser unit includes: a laser and a modulator; the control unit is configured to control the modulator to modulate multiple parameters of the laser output by the laser, the multiple parameters including frequency, and the multiple parameters further including at least one of amplitude and phase.

[0046] In a fifth aspect, the present application provides a chip, which includes a programmable logic circuit and / or program instructions, and is configured to implement the qubit manipulation method as described in any design of the third aspect when the chip runs.

[0047] In a sixth aspect, the present application provides a computer-readable storage medium, in which instructions are stored; when the instructions run on a computer, the computer is caused to execute the qubit manipulation method as described in any design of the third aspect.

[0048] In a seventh aspect, the present application provides a computer program product containing instructions, which causes a computer to execute the qubit manipulation method as described in any design of the third aspect when the computer program product runs on the computer.

[0049] The effects of the second to seventh aspects above can refer to the effects of the corresponding designs in the first aspect, and the present application will not elaborate herein. Description of the Drawings

[0050] Figure 1 It is a schematic structural diagram of a qubit manipulation device provided by an embodiment of the present application;

[0051] Figure 2 It is a schematic diagram of the positions of qubits provided by an embodiment of the present application;

[0052] Figure 3 It is a schematic diagram of qubit transition provided by an embodiment of the present application;

[0053] Figure 4 It is another schematic diagram of qubit transition provided by an embodiment of the present application;

[0054] Figure 5 It is a schematic diagram of the position of the wave belly provided by an embodiment of the present application;

[0055] Figure 6 It is a schematic diagram of the position of the wave node provided by an embodiment of the present application;

[0056] Figure 7 It is a schematic diagram of the relationship between laser power and effective interaction strength provided by an embodiment of the present application;

[0057] Figure 8 It is a schematic diagram of the relationship between laser power and gate time provided by an embodiment of the present application;

[0058] Figure 9 Schematic structural diagram of another quantum bit manipulation device provided by an embodiment of the present application;

[0059] Figure 10 Schematic diagram of amplitude modulation provided by an embodiment of the present application;

[0060] Figure 11 Schematic structural diagram of another quantum bit manipulation device provided by an embodiment of the present application;

[0061] Figure 12 Schematic structural diagram of another quantum bit manipulation device provided by an embodiment of the present application;

[0062] Figure 13 Flowchart of a quantum bit manipulation method provided by an embodiment of the present application;

[0063] Figure 14 Block diagram of a control unit provided by an embodiment of the present application. Detailed implementation manners

[0064] An embodiment of the present application provides a quantum bit manipulation device. The quantum bit to be manipulated by the quantum bit manipulation device may be an ion or an atom. The quantum bit manipulation device is used to manipulate a first quantum bit and a second quantum bit to implement a quantum gate.

[0065] As Figure 1 shown, the quantum bit manipulation device includes: a control unit 01, a trapping unit 02, a first optical resonator 03, a second optical resonator 04, and a laser unit 05.

[0066] The control unit 01 is configured to control the trapping unit 02, the first optical resonator 03, the second optical resonator 04, and the laser unit 05 to implement the manipulation of the first quantum bit and the second quantum bit.

[0067] The trapping unit 02 can trap the first quantum bit and the second quantum bit to be manipulated under the control of the control unit 01. It can be understood that the control unit 01 may only control the trapping unit 02 to trap the first quantum bit and the second quantum bit, or the control unit 01 may control the trapping unit 02 to trap multiple quantum bits. In addition to the first quantum bit and the second quantum bit, the multiple quantum bits also include other quantum bits. The embodiment of the present application does not limit this. Optionally, the first quantum bit and the second quantum bit may be separated from the other quantum bits and be in different regions in the trapping unit 02, so as to avoid the influence of the manipulation laser of the first quantum bit and the second quantum bit on the other quantum bits.

[0068] Exemplarily, when both the first qubit and the second qubit are ions, the control unit 01 can control the trapping unit to trap an ion chain composed of the first qubit and the second qubit; or, the control unit 01 can control the trapping unit to trap an ion crystal including a plurality of ions, the plurality of ions including the first qubit and the second qubit, and further including other qubits other than the first qubit and the second qubit. The ion crystal can be a one-dimensional ion chain, or a two-dimensional or three-dimensional crystal. The trapping unit 02 can be an ion trap, such as a chip trap or a segmented trap, etc. The first qubit and the second qubit can be ions of the same element, or ions of different elements. The same element can be calcium (Ca), beryllium (Be), etc., and the different elements can be calcium (Ca) and beryllium (Be), etc.

[0069] The trapping unit 02 has a plurality of electrodes, and the structure located inside the trapping unit 02 can be located between the plurality of electrodes. The control unit 01 can apply voltages to the plurality of electrodes to enable the trapping unit to trap the first qubit and the second qubit. Taking the trapping unit 02 as a Paul trap as an example, the Paul trap uses an electrostatic field and an alternating electric field to trap ions. In this case, the plurality of electrodes in the trapping unit 02 can include a direct current (DC) electrode and a radio-frequency (RF) electrode. The control unit 01 can apply a DC voltage to the DC electrode to form an electrostatic field, and the control unit 01 can apply an RF voltage to the RF electrode to form an alternating electric field.

[0070] Optionally, the control unit 01 can further control the trapping unit 02 to transport the trapped first qubit and second qubit to a specified position.

[0071] Both the first optical resonator 03 and the second optical resonator 04 are optical resonators. An optical resonator includes two relatively arranged mirrors, and the two mirrors can be plane mirrors or curved mirrors (such as spherical mirrors). Light of a specific frequency transmitted into the optical resonator can reflect back and forth between the two mirrors, so that the light of the specific frequency resonates between the two mirrors, realizing the amplification of the power of the light of the specific frequency. And, light of a frequency other than the specific frequency transmitted into the optical resonator cannot resonate between the two mirrors. In the embodiments of the present application, the specific frequency can be referred to as the resonance frequency of the optical resonator. Additionally, assuming that the light of the specific frequency is a traveling wave before being transmitted into the optical resonator, then when the light of the specific frequency resonates between the two mirrors, the light of the specific frequency becomes a standing wave.

[0072] The first optical resonator 03 and the second optical resonator 04 may both be located within the trapping unit 02, for example, between multiple electrodes of the trapping unit 02. In the embodiments of the present application, the first qubit and the second qubit to be manipulated are both coupled to the target motion mode (the energy levels of the first qubit and the second qubit may be the same or different). The cavity length directions of the first optical resonator 03 and the second optical resonator 04 are not perpendicular to the motion direction of the target motion mode. In this way, the light resonating in the first optical resonator 03 and the light resonating in the second optical resonator 04 both have components in this motion direction, and can manipulate the qubits coupled to the target motion mode.

[0073] The laser unit 05 is configured to transmit, under the control of the control unit 01, the laser of the resonant frequency of each optical resonator into each optical resonator, so that the laser can resonate in the transmitted optical resonator. For example, the laser unit 05 is configured to transmit, under the control of the control unit 01, the laser of the resonant frequency of the first optical resonator 03 into the first optical resonator 03, and transmit the laser of the resonant frequency of the second optical resonator 04 into the second optical resonator 04.

[0074] In the embodiments of the present application, when the qubit manipulation device manipulates the qubits, the control unit 01 is configured to control the trapping unit 02 to trap the first qubit at a first position within the first optical resonator 03, and control the trapping unit 02 to trap the second qubit at a second position within the second optical resonator 04. It can be understood that since the first optical resonator 03 and the second optical resonator 04 are both located within the trapping unit 02, and the trapping unit 02 can trap the qubits within the trapping unit 02, therefore, the trapping unit 02 can achieve trapping the first qubit at the first position within the first optical resonator 03 and trapping the second qubit at the second position within the second optical resonator 04.

[0075] Exemplarily, the first optical resonator 03 and the second optical resonator 04 are both located between the electrodes in the trapping unit 02, as Figure 2 shown, and there is a certain angle between the cavity length directions of these two optical resonators. After the control unit 01 is configured to control the trapping unit 02 to trap the first qubit at the first position within the first optical resonator 03 and control the trapping unit 02 to trap the second qubit at the second position within the second optical resonator 04, the positions of the first qubit and the second qubit may be as Figure 2 shown.

[0076] After the control unit 01 controls the trapping unit 02 to trap the first qubit and the second qubit, the control unit 01 is used to set the cavity lengths of the first optical resonator 03 and the second optical resonator 04 so that the resonance frequency of the first optical resonator 03 includes the detuned red sideband transition frequency of the trapped first qubit, and the resonance frequency of the second optical resonator 04 includes the detuned blue sideband transition frequency of the trapped second qubit. The detuned red sideband transition frequency is the detuned red sideband transition frequency corresponding to the first optical resonator 03, and the detuned blue sideband transition frequency is the detuned blue sideband transition frequency corresponding to the second optical resonator 04.

[0077] The detuned red sideband transition frequency or the detuned blue sideband transition frequency of the trapped qubit is not only related to the qubit, but also related to the situation of the qubit being trapped. For example, the situation of the qubit being trapped can be the trap frequency applied to the qubit by the trapping unit 02 when trapping the qubit. Therefore, the control unit 01 can determine the detuned red sideband transition frequency or the detuned blue sideband transition frequency of the qubit according to the qubit and the situation of its being trapped. And the detuned red sideband transition frequency or the detuned blue sideband transition frequency of the qubit is the resonance frequency of the optical resonator where the qubit is located, and the resonance frequency of the optical resonator depends on the cavity length of the optical resonator. Therefore, the control unit can determine the cavity length of the optical resonator according to the detuned red sideband transition frequency or the detuned blue sideband transition frequency of the qubit, and set the optical resonator to this cavity length. After setting this cavity length, the light with the resonance frequency of the optical resonator can resonate in the optical resonator. The cavity length of the optical resonator refers to the distance between the two mirrors in the optical resonator.

[0078] The detuned red sideband transition frequency of the qubit is the frequency of the laser that can cause the qubit to undergo a detuned red sideband transition, and the detuned blue sideband transition frequency of the qubit is the frequency of the laser that can cause the qubit to undergo a detuned blue sideband transition. In addition to the detuned red sideband transition and the detuned blue sideband transition, the qubit can also undergo a carrier transition. Exemplarily, as Figure 3 shown, taking the interaction between the laser and the two-level ion as an example, the energy level of the ion will be affected by the motion mode coupled to the ion, and can be regarded as the energy level distribution shown in Figure 3 where |n = x> represents the motion mode of the ion coupling x phonons, Figure 3 and x in it are 0, 1, 2, 3 respectively; |↑>, |↓> represent different energy levels of the ion. From Figure 3It can be seen that the ion has two energy levels in each coupled motion mode, and the two energy levels of the ion in different coupled motion modes are different. When the laser hits the ion, if the energy level transition occurs in the coupled motion mode with unchanged motion mode of the ion, then this energy level transition is called a carrier transition; if the energy level transition occurs in the coupled motion mode with changed motion mode of the ion, then this energy level transition is called a resonant red sideband transition or a resonant blue sideband transition. Among them, if the phonon number of the coupled motion mode of the ion decreases, then this energy level transition is a resonant red sideband transition; if the phonon number of the coupled motion mode of the ion increases, then this energy level transition is a resonant blue sideband transition. The energy level reached by the detuned red sideband transition has a detuning amount compared to the energy level reached by the resonant red sideband transition, and the energy level reached by the detuned blue sideband transition also has this detuning amount compared to the energy level reached by the resonant blue sideband transition.

[0079] After the control unit 01 sets the cavity lengths of the first optical resonator 03 and the second optical resonator 04, the control unit 01 is used to control the laser unit 05 to input the laser with the resonant frequency of the first optical resonator 03 into the first optical resonator 03, and control the laser unit 05 to input the laser with the resonant frequency of the second optical resonator 04 into the second optical resonator 04. The laser with the resonant frequency of the first optical resonator 03 resonates in the first optical resonator 03 to amplify the power of the laser and change the laser from a traveling wave to a standing wave; and, during the resonance of the laser in the first optical resonator 03, it will act on the first qubit coupled to the target vibration mode, thereby realizing the manipulation of the first qubit. Similarly, the laser with the resonant frequency of the second optical resonator 04 resonates in the second optical resonator 04 to amplify the power of the laser and change the laser from a traveling wave to a standing wave; and, during the resonance of the laser in the second optical resonator 04, it will act on the second qubit coupled to the target vibration mode, thereby realizing the manipulation of the second qubit. In this way, the manipulation of the first qubit and the second qubit is realized, and during the manipulation of these two qubits, these two qubits are entangled with each other, so as to facilitate the subsequent realization of a quantum gate based on these two qubits.

[0080] In the embodiment of the present application, both the first qubit and the second qubit are coupled to the target motion mode, and the first qubit undergoes a detuned red sideband transition, and the second qubit undergoes a detuned blue sideband transition. In this case, ultimately, both the first qubit and the second qubit can undergo carrier transitions.

[0081] Exemplarily, such as Figure 4As shown, before the method provided by the embodiments of the present application is used to manipulate the first qubit and the second qubit, both the first qubit and the second qubit are coupled to a target motion mode with a phonon number of n and are in the same energy level |↓>. The energy levels of these two qubits are represented as |↓↓, n>. Here, the first arrow represents the energy level of the first qubit, and the second arrow represents the energy level of the second qubit.

[0082] Please refer to Figure 4 , if a detuned red sideband transition occurs first in one of the two qubits and a detuned blue sideband transition occurs later in the other qubit, then the energy levels of these two qubits will sequentially become energy levels with a detuning amount from |↑↓, n - 1> (the first qubit undergoes a detuned red sideband transition first) and the |↑↑, n> energy level (the second qubit undergoes a detuned blue sideband transition later); or, the energy levels of these two qubits will sequentially become energy levels with a detuning amount from |↓↑, n - 1> (the second qubit undergoes a detuned red sideband transition) and the |↑↑, n> energy level (the first qubit undergoes a detuned blue sideband transition).

[0083] If a detuned blue sideband transition occurs first in one of the two qubits and a detuned red sideband transition occurs later in the other qubit, then the energy levels of these two qubits will sequentially become energy levels with a detuning amount from |↑↓, n + 1> (the first qubit undergoes a detuned blue sideband transition first) and the |↑↑, n> energy level (the second qubit undergoes a detuned red sideband transition later); or, the energy levels of these two qubits will sequentially become energy levels with a detuning amount from |↓↑, n + 1> (the second qubit undergoes a detuned blue sideband transition) and the |↑↑, n> energy level (the first qubit undergoes a detuned red sideband transition).

[0084] It can be seen that as long as a detuned red sideband transition occurs in one of the two qubits and a detuned blue sideband transition occurs in the other qubit, the energy levels of these two qubits can be transitioned from |↓↓, n> to |↑↑, n>, achieving the effect of carrier transition of these two qubits.

[0085] After the qubit manipulation method provided by the embodiments of the present application, the control unit 01 can further control the laser unit 05 to output laser sequences (sequences in time) to these two optical resonators respectively, so as to perform subsequent operations on the qubits in these two optical resonators, and finally implement a quantum gate. Finally, the control unit can also read out the states of each qubit after applying the quantum gate by means of fluorescence readout, or perform other subsequent gate operations. Optionally, the quantum gate in the embodiments of the present application can be referred to as a quantum gate (abbreviated as MS gate) or a light shift (LS) gate, etc.

[0086] According to the above content, in the embodiments of the present application, the laser for manipulating qubits resonates in the optical resonator, so that the power of the laser is amplified. The amplification of the laser power can reduce the time required to manipulate multiple qubits and improve the implementation speed of quantum gates.

[0087] Further, after the control unit 01 controls the laser unit 05 to input the laser with the resonance frequency of the first optical resonator 03 into the first optical resonator 03, the laser resonates in the first optical resonator 03, and the first qubit can be located at the antinode position of the laser. After the control unit 01 controls the laser unit 05 to input the laser with the resonance frequency of the second optical resonator 04 into the second optical resonator 04, the laser resonates in the second optical resonator 04, and the second qubit is located at the antinode position of the laser. It can be understood that when the laser resonates in the optical resonator, the transmission waveform of the laser can be as Figure 5 shown, Figure 5 the qubit in it is located at the antinode position of the laser. When the qubit is located at a position other than the antinode of the laser, the qubit can be at a node position as shown in Figure 6 shown.

[0088] It can be understood that after the control unit 01 controls the laser unit 05 to input the laser with the resonance frequency of the first optical resonator 03 into the first optical resonator 03, the first qubit may not be located at the antinode position of the laser resonating in the first optical resonator 03. After the control unit 01 controls the laser unit 05 to input the laser with the resonance frequency of the second optical resonator 04 into the second optical resonator 04, the second qubit may not be located at the antinode position of the laser resonating in the second optical resonator 04. The embodiments of the present application do not make any limitations in this regard.

[0089] Optionally, after the control unit 01 controls the laser unit 05 to input the laser with the resonance frequency of the first optical resonator 03 into the first optical resonator 03 and controls the laser unit to input the laser with the resonance frequency of the second optical resonator 04 into the second optical resonator 04, the control unit 01 can also adjust the relationship between the qubit and the antinode position of the laser in the following manner to make the qubit located at the antinode position of the laser resonating in the optical resonator where it is located.

[0090] Exemplarily, the control unit 01 is further configured to: when the first qubit is not at the antinode position of the laser resonating in the first optical resonator 03, perform at least one first adjustment operation until the first qubit is at the antinode position of the laser resonating in the first optical resonator 03. The first adjustment operation includes: controlling the trapping unit 02 to adjust the first position (the position of the first qubit), adjusting the cavity length of the first optical resonator 03 according to the adjusted first position (so that the resonance frequency of the first optical resonator includes the detuned red sideband transition frequency of the currently trapped first qubit), and controlling the laser unit 05 to input into the first optical resonator 03 the laser with the resonance frequency of the first optical resonator after adjusting the cavity length.

[0091] The control unit 01 is further configured to: when the second qubit is not at the antinode position of the laser resonating in the second optical resonator 04, perform at least one second adjustment operation until the second qubit is at the antinode position of the laser resonating in the second optical resonator 04; the second adjustment operation includes: controlling the trapping unit 02 to adjust the second position (the position of the second qubit), adjusting the cavity length of the second optical resonator 04 according to the adjusted second position (so that the resonance frequency of the second optical resonator includes the detuned red sideband transition frequency of the currently trapped second qubit), and controlling the laser unit 05 to input into the second optical resonator 04 the laser with the resonance frequency of the second optical resonator after adjusting the cavity length.

[0092] It can be seen that after the control unit 01 controls the laser unit 05 to input laser into the optical resonator each time, it is necessary to detect whether the qubit in the optical resonator is located at the antinode position of the laser resonating in the optical resonator. If the qubit in the optical resonator is located at the antinode position of the laser resonating in the optical resonator, there is no need to change the position of the qubit, change the cavity length of the optical resonator, and change the frequency of the laser input into the optical resonator by the laser unit 05. If the qubit in the optical resonator is not at the antinode position of the laser resonating in the optical resonator, it is necessary to change the position of the qubit, change the cavity length of the optical resonator, and change the frequency of the laser input into the optical resonator by the laser unit 05.

[0093] Exemplarily, when the control unit 01 detects whether the qubit in the optical resonator is located at the antinode position of the laser resonating in the optical resonator, it can control the laser unit 05 to transmit the laser of the resonance frequency of the optical resonator into the optical resonator for a π (pi) time, so that the laser acts on the qubit (in the ground state) in the optical resonator for a π (pi) time. This π time is the π time of the frequency of the laser resonating in the optical resonator. After that, the control unit 01 can control the laser unit 05 to emit a probe light to the qubit, and determine the population of the qubit according to the fluorescence scattered by the qubit based on the probe light. When the population of the qubit is basically in the dark state, it indicates that the qubit is approximately located at the antinode position of the laser resonating in the optical resonator; when the population of the qubit is basically in the bright state, it indicates that the qubit is approximately located at the node position of the laser resonating in the optical resonator.

[0094] Optionally, the control unit 01 can first detect whether the first qubit is located at the antinode position of the laser resonating in the first optical resonator 03. When it is determined that the first qubit is not located at the antinode position of the laser resonating in the first optical resonator 03, the control unit 01 performs the above-mentioned at least one first adjustment operation until the first qubit is located at the antinode position of the laser resonating in the first optical resonator 03. After that, the control unit 01 then detects whether the second qubit is located at the antinode position of the laser resonating in the second optical resonator 04; when it is determined that the second qubit is not located at the antinode position of the laser resonating in the second optical resonator 04, the control unit 01 performs the above-mentioned at least one second adjustment operation until the second qubit is located at the antinode position of the laser resonating in the second optical resonator 04.

[0095] Alternatively, the control unit 01 can first detect whether the second qubit is located at the antinode position of the laser resonating in the second optical resonator 04. When it is determined that the second qubit is not located at the antinode position of the laser resonating in the second optical resonator 04, the control unit 01 performs the above-mentioned at least one second adjustment operation until the second qubit is located at the antinode position of the laser resonating in the second optical resonator 04. After that, the control unit 01 then detects whether the first qubit is located at the antinode position of the laser resonating in the first optical resonator 03; when it is determined that the first qubit is not located at the antinode position of the laser resonating in the first optical resonator 03, the control unit 01 performs the above-mentioned at least one first adjustment operation until the first qubit is located at the antinode position of the laser resonating in the first optical resonator 03.

[0096] When the qubit is located at the antinode position of the laser resonating in the optical resonator where it is located, the power amplification effect of the laser is better, and the error suppression effect on the quantum gate is better. In the embodiments of the present application, the first qubit is located at the antinode position of the laser resonating in the first optical resonator 03, and the second qubit is located at the antinode position of the laser resonating in the second optical resonator 04 as an example. Optionally, it may also be that the first qubit is located at the antinode position of the laser resonating in the first optical resonator 03, and the second qubit is not located at the antinode position of the laser resonating in the second optical resonator 04; or, the first qubit is not located at the antinode position of the laser resonating in the first optical resonator 03, and the second qubit is located at the antinode position of the laser resonating in the second optical resonator 04.

[0097] After the first qubit is located at the antinode position of the laser resonating in the first optical resonator 03 and the second qubit is located at the antinode position of the laser resonating in the second optical resonator 04, the control unit 01 can control the laser unit 05 to output the aforementioned laser sequence to these two optical resonators respectively.

[0098] According to the foregoing introduction, during the process of the laser for manipulating the qubit resonating in the optical resonator, the laser changes from a traveling wave to a standing wave. Within the error range of the quantum gate, the reduction of the time required to manipulate multiple qubits by the traveling wave has an upper limit, while the reduction of the time required to manipulate multiple qubits by the standing wave can have no upper limit. Therefore, changing the laser for manipulating the qubit from a traveling wave to a standing wave helps to improve the implementation speed of the quantum gate.

[0099] Exemplarily, assume that the effective interaction strength of the laser for manipulating the qubit (the strength of the interaction between the spin of the qubit and the phonon) is positively correlated with: the improvement strength of the implementation speed of the quantum gate by the laser, and negatively correlated with the error of the quantum gate. Then, the relationship between the effective interaction strength and the laser power when the laser is a traveling wave and a standing wave respectively can be as Figure 7 shown. From Figure 7It can be seen that when the laser is a traveling wave, the effective interaction strength increases with the increase of the laser power, but there is a certain upper limit. When the laser is a standing wave, the effective interaction strength increases with the increase of the laser power and can have no upper limit. This is because when the power of the traveling wave increases to a certain extent, further increasing the power of the traveling wave will lead to an increase in the error of the quantum gate (which is related to the far-resonant carrier transition in the Hamiltonian of the traveling wave). Therefore, within the error range of the quantum gate, the power of the traveling wave can only be increased to a finite power, resulting in a relatively limited improvement in the speed of the quantum gate. When the power of the standing wave increases to a certain extent, further increasing the power of the standing wave will not lead to an increase in the error of the quantum gate. Therefore, within the error range of the quantum gate, the power of the standing wave can be increased to the required power as needed to achieve the required improvement in the speed of the quantum gate.

[0100] Exemplarily, assuming that the quantum bit manipulation device provided in the embodiment of the present application does not include the above optical resonator, then the Hamiltonian can be written as: where the second term is used to characterize the detuning of the far-resonant carrier transition in the Hamiltonian and is a source of error in the implementation of the quantum gate.

[0101] In the interaction picture, the Hamiltonian can be written as: where,

[0102] In the above formula, is the reduced Planck constant; η is a parameter (which can be called the Lamb-Dicke parameter), generally much less than 1, such as 0.05; Ω is the Rabi frequency, the square of which is proportional to the laser power; δ is the detuning amount (such as δ = 1.1 MHz); t is the action time of the Hamiltonian, a, a + are the creation and annihilation operators of the target motion mode; ω m is the frequency of the target motion mode;

[0103]

[0104]

[0105] J0, J2 are Bessel functions. Ω SDF reflects the effective interaction strength.

[0106] According to it can be known that under the condition of constant detuning amount, the effective interaction strength has an upper limit with the increase of the laser power (i.e., the increase of Ω).

[0107] And the quantum bit manipulation device provided in the embodiment of the present application includes the above optical resonator. In this case, the Hamiltonian can be written as:

[0108]

[0109] Among them, Δφ reflects the phase of the standing wave in the optical resonator; when the qubit is located at the antinode position of the standing wave, Δφ = 0, and the error term brought by the far-off-resonance carrier transition in the Hamiltonian disappears. Therefore, this error can be theoretically corrected. At this time, the effective interaction strength in the Hamiltonian can be expressed as: Ω SDF = ηΩ. It can be seen that there is no upper limit to the increase of this effective interaction strength with the increase of the laser power (i.e., the increase of Ω).

[0110] Exemplarily, Figure 8 shows the relationship between the power of a standing wave and the shortest duration (which can be called the gate time) required to implement the MS gate. From Figure 8 it can be seen that when the power of the standing wave is about 0.1 - 1 mW, the shortest duration required to implement the MS gate is in the order of dozens of microseconds, which is roughly in the same order of magnitude as the shortest duration required to implement the MS gate with a traveling wave. When it is necessary to compress the shortest duration required to implement the MS gate to the microsecond or sub-microsecond order of magnitude, the power of the standing wave is about 1 - 100 W. This power is relatively large, and it is difficult for the laser unit to emit a laser with this power. However, through the action of the optical resonator in this application, the laser with a lower power emitted by the laser unit can be power-amplified to obtain a laser (standing wave) with a power of about 1 - 100 W. When it is necessary to further enhance the power amplification effect of the optical resonator on the laser, the reflectivity of the mirror in the optical resonator can be increased. In this way, the power of the laser emitted by the laser unit can be amplified by hundreds or thousands, thereby significantly improving the implementation speed of the MS gate.

[0111] In addition, it takes a certain amount of time for the power of the laser resonating in the optical resonator to decay to 0. This decay time is approximately L / (c(1 - R)), where L represents the cavity length of the optical resonator, c represents the speed of light, and R represents the reflectivity of the mirror in the optical resonator for light with the resonant frequency of the optical resonator. The decay time in the embodiments of this application is much less than the time required to implement the quantum gate. Therefore, the laser resonating in the optical resonator does not affect the above laser sequence. Exemplarily, when L is 2 cm and R is 99% - 99.9%, the decay time is approximately 7 - 70 ns, and the power amplification factor of the laser resonating in the optical resonator is approximately 102 - 103. If the power of the laser input into the optical resonator by the laser unit is approximately dozens of mW, the power of the amplified laser in the optical resonator is approximately 1 - 10 W, and the time required to implement the quantum gate is about 1 μs. It can be seen that the decay time is much less than the time required to implement the quantum gate, so the decay time can be almost ignored and does not need to be particularly considered when designing the laser sequence.

[0112] Furthermore, please refer to Figure 9 inFigure 1 Based on the qubit manipulation device shown, the qubit manipulation device may further include a first displacement unit 06 and a second displacement unit 07. The first displacement unit 06 and the second displacement unit 07 may be located inside the trapping unit 02 or outside the trapping unit 02. Figure 9 Taking the case where the first displacement unit 06 and the second displacement unit 07 are located inside the trapping unit 02 as an example. The first displacement unit 06 is connected to two mirrors in the first optical resonator 03, and the second displacement unit 07 is connected to two mirrors in the second optical resonator 04. When the control unit 01 sets or adjusts the cavity length of the first optical resonator 03, it can control the first displacement unit 06 to change the position of at least one mirror in the first optical resonator 03 to set or adjust the distance between the two mirrors in the first optical resonator 03; when the control unit 01 sets or adjusts the cavity length of the second optical resonator 04, it can control the second displacement unit 07 to change the position of at least one mirror in the second optical resonator 04 to set or adjust the distance between the two mirrors in the second optical resonator 04.

[0113] It can be understood that the qubit manipulation device may not include the first displacement unit 06 and the second displacement unit 07. For example, the control unit 01 is directly connected to two mirrors in the first optical resonator 03, and is connected to two mirrors in the second displacement unit 07 and the second optical resonator 04. In this case, the control unit 01 can directly set the cavity lengths of the first optical resonator 03 and the second optical resonator 04.

[0114] The laser unit 05 provided in the embodiment of the present application includes a laser and a modulator. The laser is used to emit the laser to be modulated; the control unit 01 is used to control the modulator to modulate the parameters (such as frequency) of the laser output by the laser to obtain the laser that the laser unit 05 needs to output. Optionally, in the embodiment of the present application, the parameters of the laser output by the laser may further include at least one of amplitude and phase in addition to frequency. It can be seen that the modulator can perform pulse shaping on the laser output by the laser. Exemplarily, when the control unit 01 needs to control the laser unit 05 to output a laser sequence, the control unit 01 is used to control the modulator to modulate the amplitude and phase of the laser output by the laser. When the control unit 01 controls the modulator to modulate the amplitude of the laser output by the laser, the laser sequences before and after amplitude modulation may be as Figure 10 shown. Optionally, the laser sequence controlled by the control unit 01 to output by the laser unit 05 can be used to reduce the error of the quantum gate, and of course, the laser sequence controlled by the control unit 01 to output by the laser unit 05 may not be used to reduce the error of the quantum gate.

[0115] For example, when the power amplification factor of the laser is low and the decay time is only dozens of nanoseconds, there is no need to specially design the above laser sequence to reduce the error of the quantum gate. On this basis, if a faster gate time is required, the decay time of dozens of nanoseconds will also cause a certain error. Therefore, through pulse shaping, the decay time factor can be additionally considered to design the pulse sequence, thereby reducing the error of the quantum gate to a certain extent and forming a non-adiabatic ultrafast quantum gate. In this way, a high-fidelity (greater than 75%) quantum gate in the sub-microsecond order can be achieved while using a lower-power input laser.

[0116] The qubit manipulation device provided by the embodiment of the present application further includes other components. For example, the qubit manipulation device further includes an imaging unit, and the control unit can control the imaging unit to detect the fluorescence scattered by each qubit based on the detection light after manipulating the qubit, so as to determine the state (spin state) of each qubit. The imaging unit may include components such as an electron-multiplying charge-coupled device (EMCCD) and a photomultiplier tube (PMT) for reading out the fluorescence scattered by the qubit.

[0117] The following will take Figure 11 and Figure 12 the qubit manipulation device shown as an example for illustration.

[0118] Exemplarily, as Figure 11 shown, in this qubit manipulation device, the control unit 01 may include: a trapping control subunit 011, an adjustment subunit 012, and a laser control subunit 013.

[0119] The trapping control subunit 011 is connected to the electrodes in the trapping unit 02, and is used to apply a voltage to the electrodes to control the trapping unit 02 to trap the qubit (such as the first qubit or the second qubit) at a specified position. The laser control subunit 013 is connected to the laser unit 05 and is used to control the laser unit 05 to output the laser it needs to output. The laser output by the laser unit 05 can be transmitted to an optical resonator (the first optical resonator 03 or the second optical resonator 04) for resonance, or it can be directly transmitted to the qubit without being transmitted to the optical resonator for resonance (such as the above detection light). The adjustment subunit 012 is connected to the displacement units (such as the first displacement unit 06 and the second displacement unit 07) and is used to control the displacement units to set the cavity length of the connected optical resonator.

[0120] When the position of the qubit needs to be changed, the trapping control subunit 011 changes the voltage applied to the electrode to control the trapping unit 02 to change the trapped position of the qubit. Accordingly, the adjustment subunit 012 controls the displacement unit to adjust the cavity length of the connected optical resonator. The laser control subunit 013 controls the frequency of the laser output by the laser unit 05. Trapping control subunit 011, adjustment subunit 012, or laser control subunit 013 is used to determine whether the position of the qubit needs to be changed. Accordingly, the subunit used to determine whether the position of the qubit needs to be changed can be connected to the laser unit 05 and the imaging system.

[0121] For example, Figure 12 As shown, Figure 11 The prison control subunit 011 in Figure 12 The system is implemented using a field programmable gate array (FPGA) and a voltage application module, which includes a digital-to-analog converter (DAC) and a resonant cavity. The voltage application module is used to apply voltage to electrodes in the trapping unit 02 based on signals from the FPGA.

[0122] Figure 11 The adjustment subunit 012 in Figure 12 The proportional-integral-differential controller (PID) in the embodiment of the present invention is implemented. The PID can control the displacement unit connected to the optical resonator to actively stabilize the optical resonator so that its resonant frequency remains consistent. The displacement unit can be a piezoelectric unit, such as a lead zirconate titanate piezoelectric ceramic transducer (PZT). Optionally, the adjustment subunit 012 can also be implemented using an FPGA and a PID. In this case, the PID implements the functions of the adjustment subunit 012 under the control of the FPGA.

[0123] Figure 11 The laser control subunit 013 in Figure 12The FPGA and modulation signal module in it are implemented. The modulation signal module is used to transmit a modulation indication signal to the modulator in the laser unit 05 according to the signal from the FPGA. The modulator is used to modulate the laser from the laser according to this modulation indication signal. Among them, the modulation signal module may include an arbitrary waveform generator (AWG) and a direct digital synthesis (DDS) sub-module. The modulation indication signal may be generated by the AWG or the DDS sub-module. The modulation indication signal output by the AWG has a waveform that can be depicted by a program, and the modulation indication signal output by the DDS is a sine signal.

[0124] The laser in the embodiment of the present application may be a narrow linewidth ultra-stable laser. The laser uses an ultra-stable cavity to feedback and stabilize the frequency, and the linewidth of the laser may be less than 10 Hz. In the embodiment of the present application, each optical resonator may have a corresponding modulator. For example, the modulator corresponding to the first optical resonator is used to modulate the laser from the laser and transmit the modulated laser to the first optical resonator 03; the modulator corresponding to the second optical resonator 04 is used to modulate the laser from the laser and transmit the modulated laser to the second optical resonator 04. The modulator in the embodiment of the present application may be an acousto-optic modulator (AOM).

[0125] The control unit 01 in the embodiment of the present application may also have other functions. For example, the control unit 01 may also control the laser unit 05 to cool and initialize the first qubit and the second qubit.

[0126] In the above embodiment, the qubit manipulation device includes the first optical resonator 03 and the second optical resonator 04 as an example. Optionally, the qubit manipulation device may also include more optical resonators. The optical resonators in the qubit manipulation device may be arranged in an array, and the corresponding displacement units (such as the above first displacement unit and second displacement unit) of each optical resonator may also be arranged in an array.

[0127] (1) In the first realizable manner of the optical resonator in the qubit manipulation device, the qubit manipulation device includes a plurality of first resonator groups, such as two first resonator groups, three first resonator groups, etc.; each first resonator group includes two optical resonators, and these two optical resonators are the above first optical resonator and second optical resonator. The detuned red sideband transition frequencies corresponding to the first optical resonators in different first resonator groups are different, and the detuned blue sideband transition frequencies corresponding to the second optical resonators in different first resonator groups are different.

[0128] The control unit 01 can control the trapping unit 02 to trap the first qubit at the first positions in the respective first optical resonators 03 (the first positions of the respective first optical resonators 03 are the same position in the trapping unit), and control the trapping unit 05 to trap the second qubit at the second positions in the respective second optical resonators 04 (the second positions of the respective second optical resonators 04 are the same position in the trapping unit 02). The control unit 01 can also set the cavity lengths of the respective first optical resonators 03 and the respective second optical resonators 04, so that the resonance frequency of each first optical resonator 03 includes the detuned red sideband transition frequency corresponding to the first optical resonator 03, and the resonance frequency of each second optical resonator includes the detuned blue sideband transition frequency corresponding to the second optical resonator 04. The control unit 01 can also control the laser unit 05 to input the laser with its resonance frequency into the respective first optical resonators 03, and control the laser unit 05 to input the laser with its resonance frequency into the respective second optical resonators 04.

[0129] In this way, the laser for manipulating the first qubit is power-enhanced in the respective first optical resonators 03, and the laser for manipulating the second qubit is power-enhanced in the respective second optical resonators 03. Moreover, the detuned red sideband transition frequencies corresponding to the first optical resonators in different first resonator groups are different, and the detuned blue sideband transition frequencies corresponding to the second optical resonators in different first resonator groups are different. For each first resonator group, the first qubit can undergo a detuned red sideband transition in the first optical resonator in the first resonator group, and the second qubit can undergo a detuned blue sideband transition in the second optical resonator in the first resonator group, achieving the effect of the carrier transitions of the first qubit and the second qubit. Under the action of multiple first resonator groups, the effect that the first qubit and the second qubit undergo multiple carrier transitions (the detuned red sideband transitions corresponding to different carrier transitions are different, and the detuned blue sideband transitions are also different) in the multiple first resonator groups can be achieved. The multiple carrier transitions can improve the robustness of qubit manipulation and reduce the error of qubit manipulation.

[0130] Optionally, when the qubit manipulation device includes multiple first resonator groups, after the laser unit 05 inputs the laser with its resonance frequency into the respective first optical resonators 03, the first qubit is at the antinode position of the laser resonating in the respective first optical resonators 03; after the laser unit 05 inputs the laser with its resonance frequency into the second optical resonators 04, the second qubit is at the antinode position of the laser resonating in the respective second optical resonators 04.

[0131] Optionally, when the qubit manipulation device includes multiple first resonator groups, the control unit 01 can perform at least one adjustment operation until the first qubit is at the antinode position of the laser resonating in each first optical resonator 03 when the first qubit is not at the antinode position of the laser resonating in each first optical resonator 03; the adjustment operation includes: controlling the trapping unit to adjust the position of the first qubit, adjusting the cavity length of each first optical resonator 03 according to the adjusted position of the first qubit, and controlling the laser unit 05 to input laser with its resonant frequency into each first optical resonator 03. The control unit 01 can perform at least one adjustment operation until the second qubit is at the antinode position of the laser resonating in each second optical resonator 04 when the second qubit is not at the antinode position of the laser resonating in each second optical resonator 04; the adjustment operation includes: controlling the trapping unit to adjust the position of the second qubit, adjusting the cavity length of each second optical resonator 04 according to the adjusted position of the second qubit, and controlling the laser unit 05 to input laser with its resonant frequency into each second optical resonator 04.

[0132] Optionally, when the qubit manipulation device includes multiple first resonator groups, the qubit manipulation device includes: a first displacement unit 06 corresponding to each first optical resonator 03, and a second displacement unit 07 corresponding to each second optical resonator 04. Each first displacement unit 06 is connected to two mirrors in the corresponding first optical resonator 03, and each second displacement unit 07 is connected to two mirrors in the corresponding second optical resonator 04; the control unit 01 is configured to control the first displacement unit 06 corresponding to the first optical resonator 03 to change the position of at least one mirror in the first optical resonator 03 when setting or adjusting the cavity length of each first optical resonator 03. The control unit 01 is configured to control the second displacement unit 07 corresponding to the second optical resonator 04 to change the position of at least one mirror in the second optical resonator 04 when setting or adjusting the cavity length of each second optical resonator 04.

[0133] (2) In the second realizable manner of the optical resonator in the qubit manipulation device, the qubit manipulation device includes: a first resonator group and a second resonator group, the first resonator group includes the above-mentioned first optical resonator 03 and second optical resonator 04, and the second resonator group includes a third optical resonator and a fourth optical resonator (not shown in the drawings); the first position is also located in the third optical resonator, and the second position is also located in the fourth optical resonator; the moving direction of the target motion mode is not perpendicular to the cavity length directions of the third optical resonator and the fourth optical resonator.

[0134] In this case, the control unit 01 is further configured to set the cavity lengths of the third optical resonator and the fourth optical resonator after the trapping unit 02 traps the first qubit at the first position and the second qubit at the second position, so that the resonance frequency of the third optical resonator includes the carrier transition frequency of the trapped first qubit, and the resonance frequency of the fourth optical resonator includes the carrier transition frequency of the trapped second qubit. After that, the control unit 01 is configured to control the laser unit to input laser with the resonance frequency of the third optical resonator into the third optical resonator, and control the laser unit to input laser with the resonance frequency of the fourth optical resonator into the fourth optical resonator.

[0135] In this way, compared with the first implementation manner described above, not only can the effect of the carrier transition of the first qubit and the second qubit be achieved by the way that the first qubit undergoes a detuned red sideband transition and the second qubit undergoes a detuned blue sideband transition. Moreover, the effect of the carrier transition of the first qubit and the second qubit can also be achieved by the way that the first qubit and the second qubit undergo a carrier transition. In this way, the robustness of qubit manipulation can also be improved, and the error of qubit manipulation can be reduced.

[0136] Optionally, when the qubit manipulation device includes the first resonator group and the second resonator group, after the laser unit 05 inputs laser with its resonance frequency into the third optical resonator, the first qubit is at the antinode position of the laser resonating in the third optical resonator; after the laser unit 05 inputs laser with its resonance frequency into the fourth optical resonator, the second qubit is at the antinode position of the laser resonating in the fourth optical resonator.

[0137] Optionally, when the qubit manipulation device includes the first resonator group and the second resonator group, the control unit 01 can perform at least one adjustment operation until the first qubit is at the antinode position of the laser resonating in the first optical resonator 03 and the first qubit is at the antinode position of the laser resonating in the third optical resonator when the first qubit is not at the antinode position of the laser resonating in the first optical resonator 03 and the first qubit is not at the antinode position of the laser resonating in the third optical resonator; the adjustment operation includes: controlling the trapping unit to adjust the position of the first qubit, adjusting the cavity lengths of the first optical resonator 03 and the third optical resonator according to the adjusted position of the first qubit, and controlling the laser unit 05 to input laser with their resonance frequencies into the first optical resonator 03 and the third optical resonator respectively.

[0138] The control unit 01 can perform at least one adjustment operation until the second qubit is at the antinode position of the laser resonating in the second optical resonator 04 and the second qubit is at the antinode position of the laser resonating in the fourth optical resonator, when the second qubit is not at the antinode position of the laser resonating in the second optical resonator 04 and the second qubit is not at the antinode position of the laser resonating in the fourth optical resonator; the adjustment operation includes: controlling the trapping unit to adjust the position of the second qubit, adjusting the cavity lengths of the second optical resonator 04 and the fourth optical resonator according to the adjusted position of the second qubit, and controlling the laser unit 05 to input lasers with their resonant frequencies into the second optical resonator and the fourth optical resonator respectively.

[0139] Optionally, when the qubit manipulation device includes a first resonator group and a second resonator group, the qubit manipulation device includes: a third displacement unit corresponding to the third optical resonator, and a fourth displacement unit corresponding to the fourth optical resonator. The third displacement unit is connected to two mirrors in the corresponding third optical resonator, and the fourth displacement unit is connected to two mirrors in the corresponding fourth optical resonator; the control unit 01 is configured to control the third displacement unit corresponding to the third optical resonator to change the position of at least one mirror in the third optical resonator when setting or adjusting the cavity length of the third optical resonator. The control unit 01 is configured to control the fourth displacement unit corresponding to the fourth optical resonator to change the position of at least one mirror in the fourth optical resonator when setting or adjusting the cavity length of the fourth optical resonator.

[0140] It can be understood that when the qubit manipulation device includes a first resonator group and a second resonator group, the number of the first resonator groups can be greater than or equal to 1.

[0141] Furthermore, in the first implementation manner and the second implementation manner of the optical resonator in the qubit manipulation device, the qubit manipulation device includes a plurality of resonator groups. For example, in the first implementation manner, the plurality of resonator groups include a plurality of first resonator groups; in this implementation manner, the plurality of resonator groups include one or more first resonator groups and a second resonator group.

[0142] Optionally, among the plurality of resonator groups in the qubit manipulation device, at least two resonator groups share at least one optical resonator. In other words, the at least one optical resonator serves as the optical resonator in one resonator group among the at least two resonator groups and also serves as the optical resonator in other resonator groups. In this way, the number of optical resonators in the qubit manipulation device can be reduced, and the structural complexity of the qubit manipulation device can be lowered.

[0143] Exemplarily, assume that in the first implementable manner of the optical resonator in the above quantum bit manipulation device, a first resonator group and another first resonator group share the first optical resonator. Then, the resonance frequencies of the first optical resonator include: the different detuned red sideband transition frequencies corresponding to the first optical resonator in these two first resonator groups. It can be seen that the resonance frequency of the shared first optical resonator has a certain bandwidth. In this case, the different detuned red sideband transition frequencies corresponding to the first optical resonator in these two first resonator groups usually differ by a small amount.

[0144] In the embodiments of the present application, the shared optical resonator is taken as an example of the first optical resonator. Optionally, the shared optical resonator can also be at least one of the first optical resonator, the second optical resonator, the third optical resonator, and the fourth optical resonator.

[0145] When the laser unit 05 transmits laser to the shared optical resonator, it can transmit lasers of multiple frequencies to the optical resonator. The lasers of multiple frequencies can be obtained by combining multiple beams of lasers with different frequencies, or the lasers of multiple frequencies can be obtained by modulating a beam of laser with one frequency into multiple frequencies by a modulator (such as an acousto-optic modulator).

[0146] Optionally, the quantum bit manipulation device can further include a third resonator group, which includes: a fifth optical resonator and a sixth optical resonator. The fifth optical resonator and the sixth optical resonator can be used to achieve Raman manipulation of the hyperfine structure energy levels of electrons. Raman manipulation is achieved by two beams of lasers that do not resonate with the internal state of the ion. As long as the frequency difference between these two beams of lasers is adjusted to be the same as the energy level frequency difference between the two target internal states of the ion, the transition of the ion between two internal states with similar frequencies can be achieved by this method. When implementing Raman manipulation, the control unit can control the laser unit to input these two beams of lasers into the fifth optical resonator and the sixth optical resonator respectively.

[0147] The embodiments of the present application further provide a quantum computer, including any quantum bit manipulation device provided by the embodiments of the present application, and the above first quantum bit and second quantum bit.

[0148] The embodiments of the present application further provide a quantum bit manipulation method, which is executed by the control unit in any quantum bit manipulation device provided by the embodiments of the present application, as Figure 13 shown, the quantum bit manipulation method includes:

[0149] S101. Control the trapping unit to trap the first qubit at a first position in the first optical resonator, and control the trapping unit to trap the second qubit at a second position in the second optical resonator; both the first qubit and the second qubit are coupled to the target motion mode, and the motion direction of the target motion mode is not perpendicular to the cavity length directions of the first optical resonator and the second optical resonator.

[0150] S102. Set the cavity lengths of the first optical resonator and the second optical resonator so that the resonance frequency of the first optical resonator includes the detuned red sideband transition frequency of the trapped first qubit, and the resonance frequency of the second optical resonator includes the detuned blue sideband transition frequency of the trapped second qubit.

[0151] S103. Control the laser unit to input laser with the resonance frequency of the first optical resonator into the first optical resonator, and control the laser unit to input laser with the resonance frequency of the second optical resonator into the second optical resonator.

[0152] Optionally, after controlling the laser unit to input laser with the resonance frequency of the first optical resonator into the first optical resonator, the first qubit is at the antinode position of the laser resonating in the first optical resonator; after controlling the laser unit to input laser with the resonance frequency of the second optical resonator into the second optical resonator, the second qubit is at the antinode position of the laser resonating in the second optical resonator.

[0153] Optionally, after S103, the qubit manipulation method provided by the embodiments of the present application further includes:

[0154] When the first qubit is not at the antinode position of the laser resonating in the first optical resonator, perform at least one first adjustment operation until the first qubit is at the antinode position of the laser resonating in the first optical resonator; the first adjustment operation includes: controlling the trapping unit to adjust the first position, adjusting the cavity length of the first optical resonator according to the adjusted first position, and controlling the laser unit to input laser with the resonance frequency of the adjusted first optical resonator into the first optical resonator.

[0155] When the second qubit is not at the antinode position of the laser resonating in the second optical resonator, perform at least one second adjustment operation until the second qubit is at the antinode position of the laser resonating in the second optical resonator; the second adjustment operation includes: controlling the trapping unit to adjust the second position, adjusting the cavity length of the second optical resonator according to the adjusted second position, and controlling the laser unit to input laser with the resonance frequency of the adjusted second optical resonator into the second optical resonator.

[0156] Optionally, the qubit manipulation device further includes: a first displacement unit and a second displacement unit. The first displacement unit is connected to two mirrors in the first optical resonator, and the second displacement unit is connected to two mirrors in the second optical resonator. In S102, the control unit can control the first displacement unit to change the position of at least one mirror in the first optical resonator to set the cavity length of the first optical resonator, and control the second displacement unit to change the position of at least one mirror in the second optical resonator to set the cavity length of the second optical resonator.

[0157] Optionally, the qubit manipulation device includes a plurality of first resonator groups; each first resonator group includes a first optical resonator and a second optical resonator; the detuned red sideband transition frequencies corresponding to the first optical resonators in different first resonator groups are different, and the detuned blue sideband transition frequencies corresponding to the second optical resonators in different first resonator groups are different.

[0158] Optionally, the qubit manipulation device includes: a first resonator group and a second resonator group. The first resonator group includes a first optical resonator and a second optical resonator, and the second resonator group includes a third optical resonator and a fourth optical resonator; a first position is located inside the third optical resonator, and a second position is located inside the fourth optical resonator; the moving direction of the target motion mode is not perpendicular to the cavity length directions of both the third optical resonator and the fourth optical resonator. The qubit manipulation method provided by the embodiments of the present application further includes: setting the cavity lengths of the third optical resonator and the fourth optical resonator so that the resonance frequency of the third optical resonator includes the carrier transition frequency of the trapped first qubit, and the resonance frequency of the fourth optical resonator includes the carrier transition frequency of the trapped second qubit; controlling the laser unit to input laser light with the resonance frequency of the third optical resonator into the third optical resonator, and controlling the laser unit to input laser light with the resonance frequency of the fourth optical resonator into the fourth optical resonator.

[0159] Optionally, at least two resonator groups in the qubit manipulation device share at least one optical resonator.

[0160] Optionally, the laser unit includes: a laser and a modulator; the control unit is used to control the modulator to modulate multiple parameters of the laser output by the laser, the multiple parameters include frequency, and the multiple parameters further include at least one of amplitude and phase.

[0161] The qubit manipulation method provided by the embodiments of the present application can refer to any of the qubit manipulation devices provided in the foregoing embodiments, and the embodiments of the present application will not be elaborated herein.

[0162] The structural block diagram of the control unit provided by the embodiments of the present application can be as Figure 14 shown, please refer to Figure 14, the control unit includes: a first control module 1101, a first setting module 1102, and a second control module 1103.

[0163] The first control module 1101 is configured to control the trapping unit to trap the first qubit at a first position in the first optical resonator, and control the trapping unit to trap the second qubit at a second position in the second optical resonator; both the first qubit and the second qubit are coupled to a target motion mode, and the motion direction of the target motion mode is not perpendicular to the cavity length directions of the first optical resonator and the second optical resonator;

[0164] The first setting module 1102 is configured to set the cavity lengths of the first optical resonator and the second optical resonator, so that the resonance frequency of the first optical resonator includes the detuned red sideband transition frequency of the trapped first qubit, and the resonance frequency of the second optical resonator includes the detuned blue sideband transition frequency of the trapped second qubit;

[0165] The second control module 1103 is configured to control the laser unit to input laser light with the resonance frequency of the first optical resonator into the first optical resonator, and control the laser unit to input laser light with the resonance frequency of the second optical resonator into the second optical resonator.

[0166] Optionally, after the second control module 1103 controls the laser unit to input laser light with the resonance frequency of the first optical resonator into the first optical resonator, the first qubit is at the antinode position of the laser light resonating in the first optical resonator;

[0167] After the second control module 1103 controls the laser unit to input laser light with the resonance frequency of the second optical resonator into the second optical resonator, the second qubit is at the antinode position of the laser light resonating in the second optical resonator.

[0168] Optionally, the control unit further includes:

[0169] A first adjustment module ( Figure 14 not shown in the figure) for performing at least one first adjustment operation until the first qubit is at the antinode position of the laser light resonating in the first optical resonator when the first qubit is not at the antinode position of the laser light resonating in the first optical resonator; the first adjustment operation includes: controlling the trapping unit to adjust the first position, adjusting the cavity length of the first optical resonator according to the adjusted first position, and controlling the laser unit to input laser light with the resonance frequency of the first optical resonator after adjusting the cavity length into the first optical resonator;

[0170] A second adjustment module ( Figure 14(not shown in the figure) is used to perform at least one second adjustment operation until the second qubit is at the antinode position of the laser resonating in the second optical resonator when the second qubit is not at the antinode position of the laser resonating in the second optical resonator; the second adjustment operation includes: controlling the trapping unit to adjust the second position, adjusting the cavity length of the second optical resonator according to the adjusted second position, and controlling the laser unit to input into the second optical resonator a laser with the resonant frequency of the second optical resonator after adjusting the cavity length;

[0171] Optionally, the qubit manipulation device further includes: a first displacement unit and a second displacement unit, the first displacement unit is connected to two mirrors in the first optical resonator, and the second displacement unit is connected to two mirrors in the second optical resonator; the first setting module 1102 is used to control the first displacement unit to change the position of at least one mirror in the first optical resonator to set the cavity length of the first optical resonator; and control the second displacement unit to change the position of at least one mirror in the second optical resonator to set the cavity length of the second optical resonator.

[0172] Optionally, the qubit manipulation device includes a plurality of first resonator groups; the first resonator group includes a first optical resonator and a second optical resonator; the detuned red sideband transition frequencies corresponding to the first optical resonators in different first resonator groups are different, and the detuned blue sideband transition frequencies corresponding to the second optical resonators in different first resonator groups are different.

[0173] Optionally, the qubit manipulation device includes: a first resonator group and a second resonator group, the first resonator group includes a first optical resonator and a second optical resonator, and the second resonator group includes a third optical resonator and a fourth optical resonator; the first position is inside the third optical resonator, and the second position is inside the fourth optical resonator; the moving direction of the target motion mode is not perpendicular to the cavity length directions of both the third optical resonator and the fourth optical resonator; the control unit may further include a second setting module and a third control module ( Figure 14 (not shown in the figure). The second setting module is used to set the cavity lengths of the third optical resonator and the fourth optical resonator so that the resonant frequency of the third optical resonator includes the carrier transition frequency of the trapped first qubit, and the resonant frequency of the fourth optical resonator includes the carrier transition frequency of the trapped second qubit; the third control module is used to control the laser unit to input into the third optical resonator a laser with the resonant frequency of the third optical resonator, and control the laser unit to input into the fourth optical resonator a laser with the resonant frequency of the fourth optical resonator.

[0174] Optionally, at least two resonator groups share at least one optical resonator.

[0175] Optionally, the laser unit includes: a laser and a modulator; a control unit is configured to control the modulator to modulate multiple parameters of the laser output by the laser, the multiple parameters including frequency, and the multiple parameters further including at least one of amplitude and phase.

[0176] It can be understood that the control unit provided in the embodiments of the present application can also be implemented by a chip.

[0177] The embodiments of the present application further provide a computer-readable storage medium, in which instructions are stored, and when the instructions run on a computer, the computer is caused to execute any method executed by the control unit provided in the embodiments of the present application.

[0178] The embodiments of the present application further provide a computer program product including instructions, and when the computer program product runs on a computer, the computer is caused to execute any method executed by the control unit provided in the embodiments of the present application.

[0179] In the above embodiments, it can be implemented in whole or in part by software, hardware, firmware, or any combination thereof. When implemented using software, it can be implemented in whole or in part in the form of a computer program product, and the computer program product includes one or more computer instructions. When the computer program instructions are loaded and executed on a computer, the processes or functions described in the embodiments of the present application are generated in whole or in part. The computer may be a general-purpose computer, a computer network, or other programmable devices. The computer instructions may be stored in a readable storage medium of the computer, or transmitted from one readable storage medium of the computer to another, for example, the computer instructions may be transmitted from one website, computer, server, or data center to another website, computer, server, or data center in a wired manner (such as coaxial cable, optical fiber, digital subscriber line) or a wireless manner (such as infrared, wireless, microwave, etc.). The readable storage medium of the computer may be any available medium that the computer can access or a data storage device such as a server or data center integrating one or more available media. The available medium may be a magnetic medium (such as a floppy disk, a hard disk, a magnetic tape), an optical medium, or a semiconductor medium (such as a solid-state drive), etc.

[0180] In the present application, terms such as "first" and "second" are only used for descriptive purposes and cannot be construed as indicating or implying relative importance. The term "at least one" means one or more, and "a plurality" means two or more, unless otherwise clearly defined. "At least one of the following" refers to any combination of these items, including any combination of single items or multiple items. For example, at least one of a, b, or c means: a, b, c, a + b, a + c, b + c, and a + b + c, these seven cases.

[0181] The various types of embodiments provided in the embodiments of the present application can all refer to each other, and the embodiments of the present application do not limit this.

[0182] In the corresponding embodiments provided in the present application, it should be understood that the disclosed devices and the like can be implemented in other constitutive manners. For example, the device embodiments described above are merely illustrative. For example, the division of modules or units is only a logical function division. In actual implementation, there can be other division methods, such as combining or integrating multiple modules or units into another system, or ignoring some features, or not executing.

[0183] As described above, only the optional implementation manners of the present application are provided, but the protection scope of the present application is not limited thereto. Any person skilled in the art within the technical scope disclosed in the present application can easily think of various equivalent modifications or substitutions, and these modifications or substitutions should all be covered within the protection scope of the present application. Therefore, the protection scope of the present application shall be subject to the protection scope of the claims.

Claims

1. A quantum bit manipulation device, characterized in that Including: A control unit, a trapping unit, a first optical resonator, a second optical resonator, and a laser unit; the control unit is configured to: Control the trapping unit to trap a first qubit at a first position within the first optical resonator, and control the trapping unit to trap a second qubit at a second position within the second optical resonator; both the first qubit and the second qubit are coupled to a target motion mode, and the motion direction of the target motion mode is not perpendicular to the cavity length directions of both the first optical resonator and the second optical resonator; Set the cavity lengths of the first optical resonator and the second optical resonator such that the resonance frequency of the first optical resonator includes the detuned red sideband transition frequency of the trapped first qubit, and the resonance frequency of the second optical resonator includes the detuned blue sideband transition frequency of the trapped second qubit; Control the laser unit to input laser light of the resonance frequency of the first optical resonator into the first optical resonator, and control the laser unit to input laser light of the resonance frequency of the second optical resonator into the second optical resonator.

2. The quantum bit manipulation device according to claim 1, wherein After the laser unit inputs laser light of the resonance frequency of the first optical resonator into the first optical resonator, the first qubit is at the antinode position of the laser light resonating within the first optical resonator; After the laser unit inputs laser light of the resonance frequency of the second optical resonator into the second optical resonator, the second qubit is at the antinode position of the laser light resonating within the second optical resonator.

3. The qubit manipulation device according to claim 1 or 2, characterized in that The control unit is further configured to: When the first qubit is not at the antinode position of the laser light resonating within the first optical resonator, perform at least one first adjustment operation until the first qubit is at the antinode position of the laser light resonating within the first optical resonator; The first adjustment operation includes: controlling the trapping unit to adjust the first position, adjusting the cavity length of the first optical resonator according to the adjusted first position, and controlling the laser unit to input laser light of the resonance frequency of the first optical resonator with the adjusted cavity length into the first optical resonator; When the second qubit is not at the antinode position of the laser light resonating within the second optical resonator, perform at least one second adjustment operation until the second qubit is at the antinode position of the laser light resonating within the second optical resonator; the second adjustment operation includes: controlling the trapping unit to adjust the second position, adjusting the cavity length of the second optical resonator according to the adjusted second position, and controlling the laser unit to input laser light of the resonance frequency of the second optical resonator with the adjusted cavity length into the second optical resonator.

4. The quantum bit manipulation device according to any one of claims 1 to 3, characterized in that, The qubit manipulation device further includes: a first displacement unit and a second displacement unit, the first displacement unit is connected to two mirrors in the first optical resonator, and the second displacement unit is connected to two mirrors in the second optical resonator; The control unit is configured to: Control the first displacement unit to change the position of at least one mirror in the first optical resonator to set the cavity length of the first optical resonator; Control the second displacement unit to change the position of at least one mirror in the second optical resonator to set the cavity length of the second optical resonator.

5. The quantum bit manipulation device according to any one of claims 1 to 4, characterized in that The qubit manipulation device includes a plurality of first resonator groups; the first resonator group includes the first optical resonator and the second optical resonator; The detuned red sideband transition frequencies corresponding to the first optical resonators in different first resonator groups are different, and the detuned blue sideband transition frequencies corresponding to the second optical resonators in different first resonator groups are different.

6. The qubit manipulation device according to any one of claims 1 to 5, characterized in that, The qubit manipulation device includes: a first resonator group and a second resonator group, the first resonator group includes the first optical resonator and the second optical resonator, the second resonator group includes a third optical resonator and a fourth optical resonator; the first position is located in the third optical resonator, and the second position is located in the fourth optical resonator; the moving direction of the target motion mode is not perpendicular to the cavity length directions of both the third optical resonator and the fourth optical resonator; The control unit is further configured to: Set the cavity lengths of the third optical resonator and the fourth optical resonator so that the resonance frequency of the third optical resonator includes the carrier transition frequency of the first qubit trapped therein, and the resonance frequency of the fourth optical resonator includes the carrier transition frequency of the second qubit trapped therein; Control the laser unit to input laser light with the resonance frequency of the third optical resonator into the third optical resonator, and control the laser unit to input laser light with the resonance frequency of the fourth optical resonator into the fourth optical resonator.

7. The qubit manipulation device according to claim 5 or 6, characterized in that, At least two resonator groups share at least one optical resonator.

8. The qubit manipulation device according to any one of claims 1 to 7, characterized in that The laser unit includes: a laser and a modulator; the control unit is configured to control the modulator to modulate multiple parameters of the laser output by the laser, the multiple parameters include frequency, and the multiple parameters further include at least one of amplitude and phase.

9. A quantum computer, characterized in that, Including the qubit manipulation device according to any one of claims 1 to 8, and the first qubit and the second qubit.

10. A method for manipulating qubits, characterized in that, The method is executed by a control unit in a qubit manipulation device, and the qubit manipulation device further includes: a trapping unit, a first optical resonator, a second optical resonator, and a laser unit; the method includes: Control the trapping unit to trap a first qubit at a first position in the first optical resonator, and control the trapping unit to trap a second qubit at a second position in the second optical resonator; both the first qubit and the second qubit are coupled to a target motion mode, and the moving direction of the target motion mode is not perpendicular to the cavity length directions of both the first optical resonator and the second optical resonator; Set the cavity lengths of the first optical resonator and the second optical resonator such that the resonance frequency of the first optical resonator includes the detuned red sideband transition frequency of the first qubit trapped therein, and the resonance frequency of the second optical resonator includes the detuned blue sideband transition frequency of the second qubit trapped therein; Control the laser unit to input laser light with the resonance frequency of the first optical resonator into the first optical resonator, and control the laser unit to input laser light with the resonance frequency of the second optical resonator into the second optical resonator.

11. The method according to claim 10, characterized in that, After controlling the laser unit to input laser light with the resonance frequency of the first optical resonator into the first optical resonator, the first qubit is at the antinode position of the laser light resonating in the first optical resonator; After controlling the laser unit to input laser light with the resonance frequency of the second optical resonator into the second optical resonator, the second qubit is at the antinode position of the laser light resonating in the second optical resonator.

12. The method according to claim 10 or 11, characterized in that After controlling the laser unit to input laser light with the resonance frequency of the first optical resonator into the first optical resonator, and controlling the laser unit to input laser light with the resonance frequency of the second optical resonator into the second optical resonator, the method further includes: When the first qubit is not at the antinode position of the laser light resonating in the first optical resonator, perform at least one first adjustment operation until the first qubit is at the antinode position of the laser light resonating in the first optical resonator; the first adjustment operation includes: controlling the trapping unit to adjust the first position, adjusting the cavity length of the first optical resonator according to the adjusted first position, and controlling the laser unit to input laser light with the resonance frequency of the first optical resonator with the adjusted cavity length into the first optical resonator; When the second qubit is not at the antinode position of the laser light resonating in the second optical resonator, perform at least one second adjustment operation until the second qubit is at the antinode position of the laser light resonating in the second optical resonator; the second adjustment operation includes: controlling the trapping unit to adjust the second position, adjusting the cavity length of the second optical resonator according to the adjusted second position, and controlling the laser unit to input laser light with the resonance frequency of the second optical resonator with the adjusted cavity length into the second optical resonator.

13. The method according to any one of claims 10 to 12, characterized in that The qubit manipulation device further includes: a first displacement unit and a second displacement unit, the first displacement unit is connected to two mirrors in the first optical resonator, and the second displacement unit is connected to two mirrors in the second optical resonator; Setting the cavity lengths of the first optical resonator and the second optical resonator includes: Controlling the first displacement unit to change the position of at least one mirror in the first optical resonator to set the cavity length of the first optical resonator; Controlling the second displacement unit to change the position of at least one mirror in the second optical resonator to set the cavity length of the second optical resonator.

14. The method according to any one of claims 10 to 13, characterized in that, The qubit manipulation device includes a plurality of first resonator groups; the first resonator group includes the first optical resonator and the second optical resonator; The detuned red sideband transition frequencies corresponding to the first optical resonators in different first resonator groups are different, and the detuned blue sideband transition frequencies corresponding to the second optical resonators in different first resonator groups are different.

15. The method according to any one of claims 10 to 14, characterized in that, The qubit manipulation device includes: a first resonator group and a second resonator group, the first resonator group includes the first optical resonator and the second optical resonator, and the second resonator group includes a third optical resonator and a fourth optical resonator; the first position is located within the third optical resonator, and the second position is located within the fourth optical resonator; the moving direction of the target motion mode is not perpendicular to the cavity length directions of both the third optical resonator and the fourth optical resonator; The method further includes: Setting the cavity lengths of the third optical resonator and the fourth optical resonator such that the resonance frequency of the third optical resonator includes the carrier transition frequency of the trapped first qubit, and the resonance frequency of the fourth optical resonator includes the carrier transition frequency of the trapped second qubit; Controlling the laser unit to input laser light with the resonance frequency of the third optical resonator into the third optical resonator, and controlling the laser unit to input laser light with the resonance frequency of the fourth optical resonator into the fourth optical resonator.

16. The method according to claim 14 or 15, characterized in that, At least two resonator groups share at least one optical resonator.

17. The method according to any one of claims 10 to 16, characterized in that The laser unit includes: a laser and a modulator; the control unit is configured to control the modulator to modulate multiple parameters of the laser output by the laser, the multiple parameters include frequency, and the multiple parameters further include at least one of amplitude and phase.

18. A chip, characterized in that, The chip includes a programmable logic circuit and / or program instructions, which are used to implement the qubit manipulation method according to any one of claims 10 to 17 when the chip runs.

19. A computer-readable storage medium, characterized in that, Instructions are stored in the computer-readable storage medium; when the instructions run on a computer, the computer is caused to execute the qubit manipulation method according to any one of claims 10 to 17.

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