Ion addressing method, device and system, storage medium and computer program product

Abstract

The invention discloses an ion addressing method, device and system, a storage medium and a computer program product, and belongs to the technical field of quantum information. The method comprises the steps that a first vortex laser beam is generated, polarized light at different positions in the first vortex laser beam is different, and different polarized light has different effects on ions; the ion trap is irradiated with a first vortex laser beam, the first vortex laser beam is used for controlling first ions in the ion trap, the first ions are located at the first position in the first vortex laser beam, and polarized light of the first vortex laser beam at the first position can change the quantum state of the first ions; however, the first vortex laser beam does not affect the quantum states of other ions except the first ion in the ion trap. According to the scheme, polarization addressing is realized by using the vortex laser beams, so that the crosstalk between ions is reduced, and the accuracy and fidelity of ion control are improved.

Description

Technical Field

[0001] This application relates to the field of quantum information technology, and particularly to an ion addressing method, device, system, storage medium, and computer program product. Background Art

[0002] Currently, quantum information technology has become an important research direction in the development of information technology. Quantum information technology is widely used in fields such as quantum computing, quantum simulation, quantum sensing, and precision measurement. A key point in quantum information technology is quantum manipulation. Quantum manipulation refers to manipulating a specific ion or simultaneously manipulating multiple ions. Here, "manipulating multiple ions" does not mean manipulating the entire ion collective, but rather manipulating some of the ions. This technology of manipulating one or more specific ions is called ion addressing technology. An important indicator of ion addressing technology is the magnitude of crosstalk. For the technology of using laser for ion addressing, the magnitude of crosstalk indicates how much the quantum states of the remaining ions change compared to before when using laser to manipulate a specific ion. The smaller the crosstalk, the higher the accuracy of ion addressing. How to improve the accuracy of ion addressing is a research hotspot in the industry. Summary of the Invention

[0003] This application provides an ion addressing method, device, system, storage medium, and computer program product, which can reduce the magnitude of crosstalk between ions by means of polarization addressing. The technical solution is as follows:

[0004] In a first aspect, an ion addressing method is provided. The method includes: generating a first vortex laser beam, where the polarization lights at different positions in the first vortex laser beam are different, and different polarization lights have different effects on ions; irradiating the ion trap with the first vortex laser beam to manipulate the first ion in the ion trap using the first vortex laser beam, where the first ion is located at a first position in the first vortex laser beam, and the polarization light of the first vortex laser beam at the first position can change the quantum state of the first ion, but the first vortex laser beam does not affect the quantum states of other ions in the ion trap except the first ion. That is, polarization addressing is achieved using the vortex laser beam, thereby reducing the magnitude of crosstalk between ions and improving the accuracy and fidelity of ion manipulation.

[0005] Optionally, a second ion in the ion trap is adjacent to the first ion, the second ion is located at a second position in the first vortex laser beam, the first position is the position in the first vortex laser beam where the intensity of ion transition is the highest, and the second position is the position in the first vortex laser beam where the intensity of ion transition is the lowest. That is, polarization addressing is combined with spatial addressing to further reduce crosstalk.

[0006] Optionally, both the first position and the second position are located within the first cross-section of the first vortex laser beam. That is, this solution can be applied to the manipulation of ions in an ion chain.

[0007] Optionally, the ions in the ion trap are in a magnetic field with a magnetic field gradient, and the magnetic field gradient causes the transition frequencies of multiple ions in the ion trap to be different. The first vortex laser beam can also cause the first ion to undergo an energy level transition, but the other ions in the ion trap except the first ion do not undergo an energy level transition. That is, polarization addressing can further combine frequency addressing to further reduce crosstalk. Combining polarization addressing, spatial addressing, and frequency addressing can theoretically minimize crosstalk to the greatest extent.

[0008] Before generating the first vortex laser beam, the method further includes: using a test beam to optimize the laser parameters to be tested, and determining the optimized laser parameters as the vortex laser parameters. The vortex laser beam generated according to the optimized laser parameters can make the crosstalk between the ion to be manipulated and the adjacent ions of the ion to be manipulated less than a first threshold. Correspondingly, generating the first vortex laser beam includes: generating the first vortex laser beam according to the above-mentioned vortex laser parameters. That is, the vortex laser parameters are calibrated before ion manipulation to ensure the performance of subsequent ion manipulation.

[0009] Optionally, the test beam includes a first Gaussian laser beam and a second vortex laser beam, the laser parameters to be tested include the first laser parameter to be tested and the second laser parameter to be tested, and the vortex laser parameters include the optimized first laser parameter and the optimized second laser parameter; using the test beam to optimize the laser parameters to be tested and determining the optimized laser parameters as the vortex laser parameters includes: generating a first Gaussian laser beam according to the first laser parameter to be tested, and using the first Gaussian laser beam to optimize the first laser parameter to be tested to obtain the optimized first laser parameter. The Gaussian laser beam generated according to the optimized first laser parameter can make the Rabi frequency of the ion to be manipulated higher than a second threshold; generating a second vortex laser beam according to the optimized first laser parameter and the second laser parameter to be tested, and using the second vortex laser beam to optimize the second laser parameter to be tested to obtain the optimized second laser parameter. That is, first use the Gaussian laser beam to optimize some laser parameters, and then use the vortex laser beam to optimize another part of the laser parameters, so as to improve the calibration efficiency and performance.

[0010] Among them, a second vortex laser beam is generated according to the optimized first laser parameters and the second laser parameters to be tested, and the second laser parameters to be tested are optimized by using the second vortex laser beam, and the optimized second laser parameters are obtained, including: generating a second vortex laser beam according to the optimized first laser parameters and the second laser parameters to be tested; irradiating the second vortex laser beam on the ion trap; reading out the quantum state of each ion in the ion trap to obtain the true quantum state of each ion; determining a test result, which characterizes the gap between the true quantum state and the expected quantum state of each ion in the ion trap; if the gap exceeds a third threshold, then aiming at reducing the gap, optimizing the second laser parameters to be tested, determining the second laser parameters after this optimization as the second laser parameters to be tested, and returning to execute the step of generating a second vortex laser beam according to the optimized first laser parameters and the second laser parameters to be tested; if the gap does not exceed the third threshold, then determining the second laser parameters after this optimization as the optimized second laser parameters included in the vortex laser parameters. That is, the vortex laser parameters are determined by means of multiple iterative optimizations.

[0011] Among them, the first laser parameters include beam pointing and / or laser frequency, and the second laser parameters include beam size and / or ion spacing. That is, first, the beam pointing and / or laser frequency are optimized by using a Gaussian laser beam, and then the beam size and / or ion spacing are optimized by using a vortex laser beam.

[0012] In a second aspect, an ion addressing device is provided, and the ion addressing device has the function of implementing the behavior of the ion addressing method in the first aspect above. The ion manipulation device includes one or more modules, and the one or more modules are used to implement the ion addressing method provided in the first aspect above.

[0013] In a third aspect, an ion addressing system is provided, and the system includes an ion trap and an ion addressing device, and the ion addressing device has the function of implementing the behavior of the ion addressing method in the first aspect above.

[0014] In a fourth aspect, an electronic device is provided, and the electronic device includes a processor and a memory. The memory is used to store a program for executing the ion addressing method provided in the first aspect above, and store data involved in implementing the ion addressing method provided in the first aspect above. The processor is configured to execute the program stored in the memory. The ion manipulation device may further include a communication bus, and the communication bus is used to establish a connection between the processor and the memory. Optionally, the electronic device may be part or all of a quantum computer.

[0015] In a fifth aspect, a computer-readable storage medium is provided. Instructions are stored in the computer-readable storage medium, and when the instructions are run on a computer, the computer is caused to execute the ion addressing method described in the first aspect above.

[0016] In a sixth aspect, a computer program product containing instructions is provided. When the computer program product is run on a computer, the computer is caused to execute the ion addressing method described in the first aspect above.

[0017] The technical effects obtained in the second, third, fourth, fifth, and sixth aspects above are similar to those obtained by the corresponding technical means in the first aspect, and will not be elaborated here. Description of the Drawings

[0018] Figure 1 is a schematic diagram of the shapes and polarization conditions of two vortex beams provided by an embodiment of the present application;

[0019] Figure 2 is an architecture diagram of an ion addressing system provided by an embodiment of the present application;

[0020] Figure 3 is a flowchart of a quantum calculation based on an ion trap provided by an embodiment of the present application;

[0021] Figure 4 is an architecture diagram of another ion addressing system provided by an embodiment of the present application;

[0022] Figure 5 is an architecture diagram of yet another ion addressing system provided by an embodiment of the present application;

[0023] Figure 6 is an architecture diagram of yet another ion manipulation system provided by an embodiment of the present application;

[0024] Figure 7 is a schematic structural diagram of an electronic device provided by an embodiment of the present application;

[0025] Figure 8 is a flowchart of an ion addressing method provided by an embodiment of the present application;

[0026] Figure 9 is a schematic diagram of the position of an ion in a vortex beam provided by an embodiment of the present application;

[0027] Figure 10 is a schematic flowchart of addressing debugging provided by an embodiment of the present application;

[0028] Figure 11 is a schematic structural diagram of an ion addressing device provided by an embodiment of the present application. Detailed Embodiments

[0029] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the following will further describe the embodiments of this application in detail with reference to the accompanying drawings.

[0030] For ease of understanding, some terms or nouns related to the embodiments of this application will be explained first.

[0031] Ion: Formed by an atom losing electrons through the ionization effect of a laser.

[0032] Ion trap: A device that traps charged ions. Generally, it fixes the position of ions in space through a specific electromagnetic field.

[0033] Quantum control: Using external signals such as lasers or microwaves to manipulate qubits. In the embodiments of this application, a qubit refers to a bit carried by an ion.

[0034] Addressing technology: Refers to the independent manipulation of a specific bit without affecting other bits.

[0035] Crosstalk: Refers to the unexpected influence on other bits when a specific bit is manipulated. In the embodiments of this application, crosstalk refers to the influence on other ions when manipulating the ion to be manipulated (also known as the addressed ion), such as the change in the quantum state.

[0036] Vortex laser beam: Briefly referred to as a vortex beam. Looking along the propagation direction of the beam, the polarization conditions at different positions in the cross-section of the vortex beam are different. A typical example is the Laguerre-Gaussian (LG) beam. Since the intensity distribution of this type of beam in the cross-section is annular and the optical phase increases linearly along the annular region, it is called a vortex beam. The embodiments of this application mainly utilize the polarization conditions at different positions in the vortex beam to independently address specific ions. Next, the principle and feasibility of using the vortex laser beam to achieve polarization addressing of ions will be introduced.

[0037] Taking the LG beam as an example, for an LG beam propagating along the z-axis with a wave number of k, an angular frequency of w, and an intensity of E0, its electric field equation can be expressed as formula (1).

[0038]

[0039] Among them, the mode equation Describes the transverse distribution of a field with a radial exponent of p (= 0, 1, 2,...) and an angular exponent of l (= 0, 1, 2,...). σ describes the direction of light polarization (when σ equals 0, it is pure linear polarization along the x-axis; when σ = ±1, it is pure circular polarization). Here, i represents the imaginary unit. In the cylindrical coordinate system {ρ, φ, z}, the mode equation can be expressed as Equation (2).

[0040]

[0041] Among them, w0 is the beam waist size of the light beam.

[0042] Figure 1 Shows the shapes and polarization states of two vortex beams of light. These two vortex beams of light are respectively represented as and The electric fields of these two vortex beams of light can be respectively expressed as Equations (3) and (4).

[0043]

[0044]

[0045] From Figure 1 it can be seen that the shapes of the above two vortex beams of light are both circular rings (i.e., the light in the cross-section presents a circular ring shape), but the polarization states are different. Specifically, the polarized light of is radially polarized light, and the polarization directions at different positions in the radially polarized light always follow the radial direction and are radially distributed. the polarized light in is azimuthally polarized light, and the polarization directions at different positions in the azimuthally polarized light are always perpendicular to the line connecting that position and the center of the light beam, forming a vector circle.

[0046] As is well known, there are various forms of the interaction between ions and lasers. Generally, they can be classified in the order of the strength of the interaction as: electric dipole transition, electric quadrupole transition, and magnetic dipole transition, etc. Generally, electric dipole transition is considered because this form of transition is relatively easy to occur, and the transition intensity mainly depends on the electric field strength felt by the ions. The intensity of the electric quadrupole transition is usually relatively weak, and the transition intensity mainly depends on the gradient of the electric field strength felt by the ions. However, in the interaction between a vortex laser beam and ions, both electric dipole transition and electric quadrupole transition exist, and even in some cases, the intensity of the electric quadrupole transition is greater than that of the electric dipole transition. The reason is that the polarization gradient of the vortex beam is large. Therefore, the embodiments of this application mainly consider the electric quadrupole transition.

[0047] According to Equation (5), the relative intensity of each transition in various laser beam excitations of multiple transitions can be calculated.

[0048]

[0049] Taking 40Ca+ ion as an example, we select two different energy levels (4 2 S 1 / 2 and 3 2 D 5 / 2 ) The difference between the two angular momentum quantum numbers J1 and J2 is ΔJ = 2, and a laser beam with a wavelength of λ of 729 nanometers (nm) is used to excite 4 2 S 1 / 2 to 3 2 D 5 / 2 The electric quadrupole transition is selected, the S state magnetic quantum number m1 = +1 / 2 is selected as the initial state, the D state magnetic quantum number m2 is selected as the final state, the difference between m1 and m2 is Δm, the beam waist size w0 is 1 micron (μm), and the relative intensity of different transitions excited by different beams at different positions is calculated and tested. The results show that the transition intensity at different positions of the same cross section of the same beam is different. For example, the transition intensity at the center position of a cross section of a vortex beam is higher, but the transition intensity on the ring slightly away from the center position is lower, wherein the transition intensity on some rings is a minimum point. For another example, the transition intensity at the center position of a vortex beam is lower, but the transition intensity on the ring slightly away from the center position is higher. For another example, there are multiple minimum points and / or maximum points of transition intensity on the same cross section of a vortex beam. It can be seen that by using positions with higher transition intensity to independently address specific ions, and placing irrelevant ions at positions with lower transition intensity, high fidelity of ion manipulation can also be achieved. For example, the ion to be controlled is placed at the maximum point of the transition intensity, and the adjacent ions of the ion to be controlled are placed at the minimum point of the transition intensity.

[0050] The above-mentioned method of manipulating ions by utilizing different polarization conditions at different positions in the vortex laser beam can be referred to as polarization addressing. Next, a brief introduction is given to spatial addressing and frequency addressing in the related technologies related to the embodiments of the present application.

[0051] First, introduce the spatial addressing technology.

[0052] The electron transitions within ions require external laser excitation, so ions not irradiated by the laser will not be affected and will not undergo transitions. Based on this idea, a spatial addressing technology route was proposed. Its approach is to focus the laser beam into an extremely small spot so that it can just illuminate a single ion without affecting nearby ions, thereby achieving independent control of the single ion.

[0053] Consider an ion trap system with only one potential well. Multiple ions are confined in the ion trap (which can be simply referred to as the trap), and usually they are arranged in a straight line to form an ion chain. To implement the spatial addressing technique, the size (i.e., diameter) of the laser beam should be at least smaller than the minimum distance between ions. Under general experimental parameters, the distance between two adjacent ions is approximately in the range of 3 to 10 micrometers. While adjusting the size of the laser beam, it is also necessary to adjust the direction of the laser beam so that it irradiates the ion to be manipulated.

[0054] In one scheme, using optical elements such as an acousto-optic deflector, a single beam is divided into several beams, and then the beams are focused by a special lens and irradiated onto each ion on the ion chain respectively. By turning on and off each beam, independent addressing of the corresponding ion can be achieved.

[0055] The spatial addressing in the related technology has at least the following disadvantages:

[0056] (1) Considering a single potential well, as the number of ions increases, the ion spacing will gradually decrease. However, there is a limit to the focusing of the laser beam. Currently, the minimum waist of the laser beam is about 1 micrometer, which means that the number of ions in the potential well cannot increase indefinitely.

[0057] (2) For a two-dimensional ion crystal, a wider scanning coverage of the laser beam is required, and the implementation difficulty is relatively high.

[0058] Next, the frequency addressing technique is introduced.

[0059] The irradiation of an external laser can cause the ions to undergo energy level transitions, but the conditions for this process are also stringent. It is required that the frequency of the laser is consistent with the frequency difference between two energy levels in the ion transition (i.e., resonance can be generated) to excite the ion transition. At the same time, the transition frequency (energy) is not constant but is affected by the external electromagnetic field. Based on the above theory, the technical route of frequency addressing is proposed, and a representative scheme among them is magnetic field gradient addressing. Its approach is to use external factors such as magnetic field gradient to stagger the frequencies of the same transitions of each ion, and then utilize the selectivity of the transition to frequency, and manipulate specific ions by setting the frequency of the laser beam.

[0060] Consider a long string of ions confined in an ion trap. By means of a permanent magnet or a coil, etc., a magnetic field linearly varying along the ion arrangement direction z can be created near the center of the potential well. The magnetic field magnitude B(z) = B_0 + kz, where k represents the magnetic field gradient and B_0 represents the magnetic field at the reference point. The reference point can be at the above-mentioned device or other positions. Since the spatial positions of different ions are different, the magnetic field magnitudes felt by different ions are different. Due to the Zeeman effect, the ion energy levels will shift in the magnetic field. Under weak field conditions, the shift amount ΔE has a linear relationship with the magnetic quantum number m and the magnetic field magnitude B, that is, ΔE ∝ mB.

[0061] Select a pair of energy levels in the ion energy levels that are sensitive to the magnetic field. The energy difference between this pair of energy levels will vary slightly with the magnitude of the magnetic field in which the ions are located. By selecting appropriate magnetic field gradient parameters, the corresponding transition frequencies of each ion can be staggered and not affect each other. In this case, the laser for manipulating the ions does not need to be focused on a single ion, but can be irradiated on the entire ion ensemble. Any ion can be manipulated by setting an appropriate laser frequency.

[0062] The magnetic field gradient addressing technology (frequency addressing) in the related art has at least the following disadvantages:

[0063] (1) As the number of ions increases and the ion chain becomes longer, the magnetic field strength in the trap also increases accordingly, making the relationship between the energy difference between ion energy levels and the magnetic field strength fall in a non-linear range, and the non-linear relationship is relatively difficult to measure and control.

[0064] (2) Ions not only have internal energy levels but also external motion energy levels. The energy of ions in the motion state is relatively small and is comparable to the energy difference generated by the magnetic field gradient. When designing a frequency addressing scheme, it is necessary to consider whether it will excite the transitions of other energy levels and affect the experiment.

[0065] As shown above, Table 1 gives the principle comparison of three technical solutions: spatial addressing, frequency addressing, and polarization addressing.

[0066] Table 1

[0067]

[0068] As can be seen from the above, this solution solves the crosstalk problem in ion addressing from a completely new perspective. Next, this solution will be introduced in detail.

[0069] First, the implementation environment of the embodiments of this application will be introduced.

[0070] Figure 2 It is the architecture diagram of an ion addressing system provided by the embodiments of this application. The ion addressing system can also be called an ion manipulation system. This system can be used to implement quantum computing based on an ion trap. This system includes a control subsystem, a laser subsystem, an electromagnetic field generating device, an ion trap (with a vacuum cavity inside, and an ion chain is confined in the vacuum cavity), and a detection device.

[0071] Among them, the control subsystem is connected to the laser subsystem and is used to control the laser subsystem to generate various laser beams, such as generating a timing sequence to control the switching of the laser beams. The control subsystem is also connected to the electromagnetic field generating device and is used to control the electromagnetic field generating device to generate an electromagnetic field, so as to confine ions in the ion trap by using the electromagnetic field, such as confining the ions into an ion chain (the spacing between ion arrangements is on the micron scale). The control subsystem is also connected to the detection device and is used to control the detection device to read the quantum states of the ions in the ion trap.

[0072] The laser subsystem is used to generate manipulation light, detection light, and ionization, cooling / pumping light under the control of the control subsystem, and irradiate the generated light to the ion trap. Among them, the manipulation light is mainly used to manipulate specific ions, and the detection light is mainly used to make the ions emit fluorescence so that the detection device can read the quantum states of the ions. The ionization light is mainly used to ionize atoms into ions. The cooling / pumping light is mainly used to cool and initialize the ions to cool the ions and initialize the internal and external states of the ions to the specified states.

[0073] The control subsystem in the embodiments of the present application includes an optical modulator, a beam splitter, etc., and may also include other devices, which are not limited in the embodiments of the present application. The laser subsystem includes multiple lasers and is used to generate various types of laser beams. The embodiments of the present application also do not limit the types and structures of the lasers. The electromagnetic field generating device includes a permanent magnet or a coil, etc., and the detection device includes an imaging optical path, a camera (such as a charge coupled device (CCD)), a photomultiplier tube (PMT), etc., and specific references can be made to related technologies.

[0074] Figure 3 is a flowchart of a quantum computing based on an ion trap provided by an embodiment of the present application. Refer to Figure 2 and Figure 3 , the basic process of quantum computing at least includes the following: the outer electrons of the heated atoms are ionized by the ionization light to form ions. In a vacuum chamber, an alternating radio frequency electric field and a direct current electric field confine multiple ions into an ion chain; the ions cooled by the cooling laser reach specific quantum states under the action of the manipulation light. Quantum computing is realized by manipulating the quantum states of the ions, and here the manipulation is mainly realized by the control subsystem to lock the optical frequency of the laser subsystem in hardware, expand and focus in space, and control the manipulation light switch in time domain. The quantum gate operation is generated by a series of timings of the manipulation light.

[0075] Figure 4 is an architecture diagram of another ion addressing system provided by an embodiment of the present application. The system includes a laser, an electronic control element, a spatial light modulator, a host computer, a timing control device, a magnet or a coil, and an ion trap (with an ion chain inside). Among them, the laser can be the aboveFigure 2 The laser in the mid-infrared photon subsystem. The electronic control component, spatial light modulator, host computer, and timing control device can be Figure 2 the devices in the control subsystem. The magnet or coil can be Figure 2 the electromagnetic field generating device in

[0076] The spatial light modulator is one of the keys in the embodiments of this application. It can fabricate any type of laser beam through the programming design of the host computer, including the vortex laser beam required by this solution. The host computer is also used to send instructions to the timing control device to generate an electrical signal sequence and transmit it to the electronic control component to control the switching of the laser beam through the electronic control component. The role of the magnet or coil is to generate a magnetic field gradient at the center of the trap. Among them, referring to Figure 5 , the electronic control component can include an acousto-optic modulator or other devices, and the timing control device can include a radio frequency (RF) source or other devices.

[0077] In the embodiments of this application, the spatial light modulator is mainly used to fabricate the vortex laser beam for realizing laser polarization addressing. This is similar to the magnetic field gradient addressing scheme, except that in the magnetic field gradient scheme, the magnetic field gradient is used to distinguish the ion transition frequencies to achieve ion addressing.

[0078] To achieve high-fidelity and low-crosstalk addressing, it is necessary to consider two aspects: "vortex beam exciting non-desired transitions" and "vortex beam exciting neighboring ions" respectively. On the one hand, according to the above description, some vortex beams will significantly excite specific transitions and are difficult to generate other transitions. Also, since the electric quadrupole transition is extremely sensitive to frequency, high-fidelity addressing can be achieved in this way. On the other hand, since there are minimum points of the transition intensity in the cross-section of some beams, placing the ions adjacent to the ions to be manipulated at the minimum points can reduce crosstalk, which is equivalent to performing spatial addressing. In this way, spatial addressing and frequency addressing act on the ions simultaneously, and the crosstalk will be further reduced. At the same time, since the magnetic field gradient generated by the magnet or coil can make the transition frequencies of adjacent ions different, therefore, frequency addressing and polarization addressing will act on the ions simultaneously, and the crosstalk will be further reduced.

[0079] It can be seen that this solution can make spatial addressing, frequency addressing, and polarization addressing act on the ions simultaneously, and the crosstalk will be greatly reduced.

[0080] Figure 6 is the architecture diagram of another ion manipulation system provided by the embodiments of this application. This system architecture includes a computing entity and a quantum computer. The computing entity is connected to the quantum computer in a wireless or wired manner. Optionally, this quantum computer includes Figure 2 or Figure 4 or Figure 5 any of the ion addressing systems shown.

[0081] Among them, the computing entity is configured to receive a quantum information processing task input by a user and provide the quantum information processing task to a quantum computer. Optionally, the computing entity is further configured to obtain an execution result of the quantum information processing task output by the quantum computer and present the output of the quantum computer to the user.

[0082] The quantum computer is configured to execute a quantum information processing task input by a user by using the ion manipulation method provided in an embodiment of the present application. For example, the quantum computer determines ions that need to be manipulated by quantum bits and operations to be performed according to the quantum information processing task, and then performs corresponding operations on these ions by using the manipulated laser after sampling and calibration in the embodiment of the present application, such as performing multi-bit quantum entanglement operations, single-bit flip operations, etc. Optionally, the quantum computer is further configured to output an execution result of the quantum information processing task to the computing entity.

[0083] Please refer to Figure 7 , Figure 7 which is a schematic structural diagram of an electronic device shown according to an embodiment of the present application. The electronic device can be a part or all of the computing entity shown in Figure 6 , or can be a part of the quantum computer. In one implementation, the electronic device includes one or more processors 701, a communication bus 702, a memory 703, and one or more communication interfaces 704.

[0084] The processor 701 is a general-purpose central processing unit (CPU), a network processor (NP), a microprocessor, or one or more integrated circuits for implementing the solution of the present application. For example, an application-specific integrated circuit (ASIC), a programmable logic device (PLD), or a combination thereof. Optionally, the above PLD is a complex programmable logic device (CPLD), a field-programmable gate array (FPGA), a generic array logic (GAL), or any combination thereof.

[0085] The communication bus 702 is used to transmit information between the above components. Optionally, the communication bus 702 is divided into an address bus, a data bus, a control bus, etc. For ease of representation, only a thick line is shown in the figure, but it does not mean that there is only one bus or one type of bus.

[0086] Optionally, the memory 703 is a read-only memory (ROM), random access memory (RAM), electrically erasable programmable read-only memory (EEPROM), optical disc (including compact disc read-only memory (CD-ROM), compressed optical disc, laser disc, digital versatile disc, Blu-ray disc, etc.), magnetic disk storage medium or other magnetic storage device, or any other medium that can be used to carry or store the desired program code in the form of instructions or data structures and can be accessed by a computer, but is not limited thereto. The memory 703 exists independently and is connected to the processor 701 through a communication bus 702, or the memory 703 is integrated with the processor 701.

[0087] The communication interface 704 uses any device such as a transceiver for communicating with other devices or communication networks. The communication interface 704 includes a wired communication interface, and optionally, also includes a wireless communication interface. Among them, the wired communication interface is, for example, an Ethernet interface, etc. Optionally, the Ethernet interface is an optical interface, an electrical interface, or a combination thereof. The wireless communication interface is a wireless local area network (WLAN) interface, a cellular network communication interface, or a combination thereof, etc.

[0088] Optionally, in some embodiments, the electronic device includes multiple processors, such as Figure 7 the processor 701 and the processor 705 shown in. Each of these processors is a single-core processor or a multi-core processor. Optionally, the processor here refers to one or more devices, circuits, and / or processing cores for processing data (such as computer program instructions).

[0089] In a specific implementation, as an embodiment, the electronic device further includes an output device 706 and an input device 707. The output device 706 communicates with the processor 701 and can display information in various ways. For example, the output device 706 is a liquid crystal display (LCD), a light emitting diode (LED) display device, a cathode ray tube (CRT) display device, or a projector, etc. The input device 707 communicates with the processor 701 and can receive user input in various ways. For example, the input device 707 is a mouse, a keyboard, a touch screen device, or a sensing device, etc.

[0090] In some embodiments, the memory 703 is used to store the program code 710 for executing the solution of this application, and the processor 701 can execute the program code 710 stored in the memory 703. The program code includes one or more software modules. In the embodiments where the electronic device becomes part of a quantum computer, the electronic device can implement the ion addressing method provided in the embodiments below Figure 8 through the program code 710 in the processor 701 and the memory 703.

[0091] It should be understood that the implementation environment and business scenarios described in the embodiments of this application are for more clearly explaining the technical solutions of the embodiments of this application, and do not constitute a limitation on the technical solutions provided in the embodiments of this application. Those skilled in the art know that with the evolution of the implementation environment and the emergence of new business scenarios, the technical solutions provided in the embodiments of this application are equally applicable to similar technical problems.

[0092] Figure 8 is a flowchart of an ion addressing method provided in the embodiments of this application. This method is applied to an ion addressing system. Optionally, the ion manipulation system is Figure 2 or Figure 4 or Figure 5 any of the ion addressing systems shown. Please refer to Figure 8 and the method includes the following steps.

[0093] Step 801: Generate a first vortex laser beam. The polarization lights at different positions in the first vortex laser beam are different, and different polarization lights have different effects on ions.

[0094] As can be seen from the above, the embodiments of this application mainly use the vortex laser beam to achieve frequency addressing of ions. In a specific implementation, the ion addressing system generates a first vortex laser beam. For example, the laser in the system generates a second Gaussian laser beam and irradiates the second Gaussian laser beam to a spatial light modulator. The spatial modulator modulates the received Gaussian laser beam to generate the first vortex laser beam.

[0095] Among them, the first vortex laser beam can be any vortex laser beam that can be used for ion addressing. Here, being able to be used for ion addressing means that the polarization conditions at different positions in the beam are different.

[0096] Step 802: Irradiate the first vortex laser beam to the ion trap to manipulate the first ion in the ion trap by using the first vortex laser beam. Among them, the first ion is located at the first position in the first vortex laser beam, and the polarization light of the first vortex laser beam at the first position can change the quantum state of the first ion, but the first vortex laser beam does not affect the quantum states of other ions in the ion trap except the first ion.

[0097] That is, after generating the first vortex laser beam, the first vortex laser beam is irradiated on the ion trap to independently address the first ion without affecting the quantum states of the remaining ions. Here, "without affecting" means that the quantum states of the remaining ions do not change or the change amount is less than the fourth threshold. The fourth threshold can be determined according to the fidelity requirement of ion addressing. For example, the fourth threshold is 5% or 10% or other relatively small values.

[0098] As can be seen from the above, in this solution, polarization addressing can be combined with spatial addressing. For example, the second ion in the ion trap is adjacent to the first ion, and the second ion is located at the second position in the first vortex laser beam. The first position is the position in the first vortex laser beam where the intensity of ion transition is the highest, and the second position is the position in the first vortex laser beam where the intensity of ion transition is the lowest.

[0099] Exemplarily, as Figure 9 shown in the five ions in the ion chain, the third ion among these five ions is located at the position in the first vortex laser beam where the intensity of ion transition is the highest, that is, the maximum point of the transition intensity, while the second ion and the fourth ion are located at the positions in the first vortex laser beam where the intensity of ion transition is the lowest, that is, the minimum point of the transition intensity.

[0100] It should be understood that in specific implementation, the second ion adjacent to the first ion may also be located at other positions with relatively small transition intensities except the above minimum points. Similarly, the first ion may also be located at other positions with relatively large transition intensities except the above maximum points, as long as the fidelity requirement of ion addressing is satisfied.

[0101] Optionally, if this solution is applied to the manipulation of ions in an ion chain, then both the above first position and the second position are located in the first cross-section of the first vortex laser beam. For example, the above Figure 9 shown five ions (the five small black circles in the figure) are all located in one cross-section.

[0102] Of course, this solution can also be applied to the manipulation of ions in a two-dimensional or three-dimensional ion crystal. Then, the above first position and the second position may be located in different cross-sections of the first vortex laser beam.

[0103] As can be seen from the above, in this solution, polarization addressing can also be combined with frequency addressing. For example, in the embodiment of the present application, the ions in the ion trap are in a magnetic field with a magnetic field gradient. The magnetic field gradient makes the transition frequencies of multiple ions in the ion trap different. The first vortex laser beam can also cause the first ion to undergo an energy level transition, but the other ions in the ion trap except the first ion do not undergo an energy level transition.

[0104] Among them, the frequency of the first vortex laser beam is determined according to the transition frequency of the first ion. For example, the frequency of the first vortex laser beam can resonate with the transition frequency of the first ion.

[0105] Under the dual selection of laser frequency and laser polarization, the addressed ion will jump to the specified state with high fidelity rather than other dark states. For other ions except the addressed ion, under the dual protection of laser frequency (non-resonant) and laser polarization (polarization gradient light), they are hardly affected at all.

[0106] In specific implementation, a pair of energy levels can be selected as a pair of qubits according to the actual situation. For example, two different Zeeman energy levels can be selected as a pair of qubits. Here, an example is given for demonstration. Select as a pair of qubits. The change in magnetic quantum number for the transition between these two energy levels is Δm = 2. Select a beam with a wavelength λ of 729 nm, a beam waist size w0 of 1 μm, and σ = +1. The intensity distribution of the beam that excites the Δm = 2 transition is shown in Figure 9 . As described above, Figure 9 also shows the relative positions of each ion in the ion chain with respect to the vortex beam used for ion addressing. It can be seen that the two ions adjacent to the central ion (i.e., the third ion) on the left and right are exactly at the minimum of the excitation transition intensity. At this time, the ion spacing d is approximately equal to the beam waist size w0, which is 1 μm. In actual manipulation, generally, the beam size is determined according to the ion spacing. This operation is simple and reliable. Here, it mainly shows that the ion spacing is approximately equal to the beam size. Of course, if possible, the ion spacing can also be adjusted according to the beam size.

[0107] After testing, Figure 9 the ratio of the transition intensity between the central ion and the adjacent ion in

[0108] is greater than 10:1. If the vortex beam is replaced with a Gaussian beam, then the ratio of the transition intensity between the central ion and the adjacent ion may theoretically be e^2:1 ≈ 7.4:1. That is to say, the vortex beam can reduce the crosstalk of ion addressing and improve the fidelity. If the transition frequency difference caused by the magnetic field gradient is also considered, when the addressed ion is excited to jump due to frequency resonance, other ions are non-resonant and do not excite transitions. Then, the transition intensity of other ions will be reduced by two to three orders of magnitude, and the crosstalk will be further reduced.The first ion in the ion trap is manipulated using a first vortex laser beam for quantum computing. It should be understood that in this article, the process of ion addressing is introduced by taking the manipulation of one ion (i.e., the first ion) as an example. In actual quantum computing, it is possible to manipulate only a single ion, such as performing a single-bit flip operation on a certain ion to form a qubit. It is also possible to need to manipulate multiple ions simultaneously, such as performing a two-bit quantum entanglement operation on two ions to form two qubits. For each ion to be manipulated, independent addressing can be performed according to the above steps 901 to 902 to perform a complete quantum computing.

[0109] The above has introduced the process of using a vortex beam for ion addressing to perform quantum computing. To ensure the accuracy of ion addressing, it is usually necessary to ensure that the laser parameters are accurate. Then, before performing quantum computing, the laser parameters can be calibrated to obtain the vortex laser parameters, and the above first vortex laser beam can be generated according to the calibrated vortex laser parameters. Next, the process of laser parameter calibration will be introduced.

[0110] Before generating the first vortex laser beam, the vortex laser parameters can be determined by parameter tuning.

[0111] For example, a test beam is used to tune the laser parameters to be tested, and the tuned laser parameters are determined as the vortex laser parameters. The vortex laser beam generated according to the tuned laser parameters can make the crosstalk between the ion to be manipulated and the adjacent ions of the ion to be manipulated less than a first threshold.

[0112] Among them, the test beam includes a second vortex laser beam. The second vortex laser beam is generated according to the laser parameters to be tested, and the laser parameters to be tested are tuned using the second vortex laser beam, and the tuned laser parameters are determined as the vortex laser parameters.

[0113] The tuning here includes multiple iterative tunings. That is, the laser parameters to be tested are gradually tuned to a state where the crosstalk between ions is low through multiple iterative tunings.

[0114] Optionally, to improve the calibration efficiency, first, a common Gaussian laser beam is used to tune a part of the laser parameters, and then a vortex laser beam is used to tune another part of the laser parameters. Briefly speaking, first, a coarse tuning is performed using a Gaussian beam, and then a fine tuning is performed using a vortex beam.

[0115] In one implementation, the test beam includes a first Gaussian laser beam and a second vortex laser beam. The laser parameters to be tested include the first laser parameter to be tested and the second laser parameter to be tested. The vortex laser parameters include the optimized first laser parameter and the optimized second laser parameter. First, generate the first Gaussian laser beam according to the first laser parameter to be tested, and use the first Gaussian laser beam to optimize the first laser parameter to be tested, obtaining the optimized first laser parameter. The Gaussian laser beam generated according to the optimized first laser parameter can make the Rabi frequency of the ions to be manipulated higher than the second threshold. Then, generate the second vortex laser beam according to the optimized first laser parameter and the second laser parameter to be tested, and use the second vortex laser beam to optimize the second laser parameter to be tested, obtaining the optimized second laser parameter. Briefly speaking, first use the Gaussian beam to optimize the first laser parameter, and obtain the optimized first laser parameter when the Rabi frequency of the ions to be manipulated is higher than the second threshold (such as the highest). Then use the vortex beam to optimize the second laser parameter, and obtain the optimized second laser parameter when the magnitude of the crosstalk between ions is less than the first threshold (such as the minimum).

[0116] Among them, the process of optimizing the first laser parameter and the process of optimizing the second laser parameter may both require multiple iterative optimizations. Next, the process of multiple iterative optimizations will be introduced.

[0117] The implementation process of generating the first Gaussian laser beam according to the first laser parameter to be tested and using the first Gaussian laser beam to optimize the first laser parameter to be tested, obtaining the optimized first laser parameter includes: generating the first Gaussian laser beam according to the first laser parameter to be tested; irradiating the first Gaussian laser beam on the ion trap; determining the interaction result between the first Gaussian laser beam and each ion in the ion trap; if the interaction result does not meet the expected result, then aiming to narrow the gap between the interaction result and the expected result, optimize the first laser parameter to be tested, determine the first laser parameter to be tested after this optimization as the first laser parameter to be tested, and return to execute the step of generating the first Gaussian laser beam according to the first laser parameter to be tested; if the interaction result meets the expected result, then determine the first laser parameter after this optimization as the optimized first laser parameter included in the vortex laser parameters.

[0118] Among them, the first laser parameters include the beam pointing and / or the laser frequency. Of course, other parameters can also be included. Taking the first laser parameters including the beam pointing and the laser frequency as an example, the above interaction result indicates whether the first Gaussian laser beam points to the desired direction and whether the Rabi frequency of the ion to be manipulated is higher than the second threshold. The desired direction can be the direction pointing to the central ion of the ion chain. Of course, the desired direction can also deviate from the direction pointing to the central ion. The second threshold can be determined based on experience or through theoretical analysis. The specific implementation method for calibrating (i.e., optimizing) the beam pointing and the laser frequency can also refer to the related technology and will not be elaborated here.

[0119] After the optimization of the first laser parameters is completed, a second vortex laser beam is generated according to the optimized first laser parameters and the second laser parameters to be tested, and the second laser parameters to be tested are optimized by using the second vortex laser beam to obtain the optimized second laser parameters. The specific implementation process includes: generating a second vortex laser beam according to the optimized first laser parameters and the second laser parameters to be tested; irradiating the second vortex laser beam on the ion trap; reading out the quantum state of each ion in the ion trap to obtain the true quantum state of each ion; determining the test result, and the test result characterizes the gap between the true quantum state and the desired quantum state of each ion in the ion trap; if the gap exceeds the third threshold, then aiming at reducing the gap, optimize the second laser parameters to be tested, and determine the optimized second laser parameters after this optimization as the second laser parameters to be tested, and return to execute the step of generating a second vortex laser beam according to the optimized first laser parameters and the second laser parameters to be tested; if the gap does not exceed the third threshold, then determine the optimized second laser parameters after this optimization as the optimized second laser parameters included in the vortex laser parameters.

[0120] Among them, in order to ensure the high fidelity of ion addressing, the gap between the true quantum state and the desired quantum state of each ion in the ion trap after the last debugging does not exceed the third threshold. The third threshold can be determined based on experience, such as according to the fidelity requirements of the ions.

[0121] As can be seen from the above, the first Gaussian laser beam is mainly used to optimize the beam pointing and / or the laser frequency, and then the second vortex laser beam is mainly used to optimize the beam size and / or the ion spacing. That is, the second laser parameters include the beam size and / or the ion spacing. For example, the first vortex laser beam generated according to the optimized vortex laser parameters can make the first ion (i.e., the addressed ion) located at the central position of the first vortex laser beam, and the second ion (the ion adjacent to the addressed ion) located at the position where the transition intensity excited in the first vortex laser beam is the smallest.

[0122] Figure 10It is a schematic flow diagram of addressing debugging provided by an embodiment of the present application. This addressing debugging is to optimize laser parameters. Refer to Figure 10 , after restricting the ion chain in the vacuum chamber, addressing debugging is performed to determine the vortex laser parameters. Quantum computing is performed after the addressing debugging. Among them, the number of addressing includes cooling initialization, vortex laser calibration, qubit manipulation, and quantum state detection. Cooling initialization is used to cool the ions and initialize the internal and external states of the ions. Vortex laser calibration is to generate a test beam and irradiate the test beam on the ion trap. Qubit manipulation is to use the test beam irradiated on the ion trap to manipulate the ions. Quantum state detection is to read out the quantum states of each ion in the ion trap to obtain the true quantum state of each ion. Through feedback optimization, the gap between the true quantum state of each ion and the desired quantum state is gradually reduced to not exceed the third threshold, thereby completing the addressing debugging.

[0123] In summary, in the embodiment of the present application, different polarized lights at different positions in the first vortex laser beam are used to address the ions. Among them, when using the first vortex laser beam to manipulate the first ion in the ion trap, the quantum state of the first ion will change, but the first vortex laser beam does not affect the quantum states of other ions in the ion trap except the first ion. In this way, the crosstalk between the first ion and other ions is small, and the fidelity and accuracy of ion manipulation are high. At the same time, polarization addressing can also be combined with spatial addressing and frequency addressing, and the three act on the ions together, theoretically being able to maximize the addressing performance.

[0124] Figure 11 It is a schematic structural diagram of an ion addressing device provided by an embodiment of the present application. This ion manipulation device can be implemented by software, hardware, or a combination of both to become part or all of an ion addressing system. This ion addressing system can be Figure 2 , Figure 4 or Figure 5 the ion addressing system shown. Refer to Figure 11 , this ion manipulation device includes: a laser generation module 1101 and a laser transmission module 1102.

[0125] The laser generation module 1101 generates a first vortex laser beam. The polarized lights at different positions in the first vortex laser beam are different, and different polarized lights have different effects on the ions;

[0126] The laser transmission module 1102 is used to irradiate the first vortex laser beam on the ion trap to manipulate the first ion in the ion trap with the first vortex laser beam. Among them, the first ion is located at the first position in the first vortex laser beam, and the polarized light of the first vortex laser beam at the first position can change the quantum state of the first ion, but the first vortex laser beam does not affect the quantum states of other ions in the ion trap except the first ion.

[0127] Optionally, a second ion in the ion trap is adjacent to the first ion, the second ion is located at a second position in the first vortex laser beam, the first position is the position in the first vortex laser beam where the intensity of the ion transition is the highest, and the second position is the position in the first vortex laser beam where the intensity of the ion transition is the lowest.

[0128] Optionally, both the first position and the second position are located in a first cross-section of the first vortex laser beam.

[0129] Optionally, the ions in the ion trap are in a magnetic field with a magnetic field gradient, the magnetic field gradient causes a difference in the transition frequencies of multiple ions in the ion trap, the first vortex laser beam can also cause the first ion to undergo an energy level transition, but other ions in the ion trap except the first ion do not undergo an energy level transition.

[0130] Optionally, the device further includes:

[0131] A parameter tuning module, configured to tune the laser parameters to be tested by using a test beam, determine the tuned laser parameters as the vortex laser parameters, and the vortex laser beam generated according to the tuned laser parameters can make the crosstalk between the ion to be manipulated and the adjacent ions of the ion to be manipulated less than a first threshold;

[0132] A laser generation module 1101, including:

[0133] A first generation sub-module, configured to generate a first vortex laser beam according to the vortex laser parameters.

[0134] Optionally, the test beam includes a first Gaussian laser beam and a second vortex laser beam, the laser parameters to be tested include the first laser parameter to be tested and the second laser parameter to be tested, and the vortex laser parameters include the tuned first laser parameter and the tuned second laser parameter;

[0135] The parameter tuning module includes:

[0136] A first tuning sub-module, configured to generate a first Gaussian laser beam according to the first laser parameter to be tested, and use the first Gaussian laser beam to tune the first laser parameter to be tested to obtain the tuned first laser parameter, and the Gaussian laser beam generated according to the tuned first laser parameter can make the Rabi frequency of the ion to be manipulated higher than a second threshold;

[0137] A second tuning sub-module, configured to generate a second vortex laser beam according to the tuned first laser parameter and the second laser parameter to be tested, and use the second vortex laser beam to tune the second laser parameter to be tested to obtain the tuned second laser parameter.

[0138] Optionally, the second tuning sub-module is specifically configured to:

[0139] Generate a second vortex laser beam according to the tuned first laser parameter and the second laser parameter to be tested;

[0140] Irradiate the ion trap with the second vortex laser beam;

[0141] Read out the quantum state of each ion in the ion trap to obtain the true quantum state of each ion;

[0142] Determine the test result, where the test result characterizes the gap between the true quantum state and the expected quantum state of each ion in the ion trap;

[0143] If the gap exceeds a third threshold, then aiming at reducing the gap, tune the second laser parameter to be tested, determine the tuned second laser parameter after this tuning as the second laser parameter to be tested, and return to execute the step of generating a second vortex laser beam according to the tuned first laser parameter and the second laser parameter to be tested;

[0144] If the gap does not exceed the third threshold, then determine the tuned second laser parameter after this tuning as the tuned second laser parameter included in the vortex laser parameter.

[0145] Optionally, the first laser parameter includes a beam pointing direction and / or a laser frequency, and the second laser parameter includes a beam size and / or an ion spacing.

[0146] In the embodiments of the present application, ion addressing is performed by using the polarized light at different positions in the first vortex laser beam to act on different ions. Among them, when using the first vortex laser beam to manipulate the first ion in the ion trap, the quantum state of the first ion will change, but the first vortex laser beam does not affect the quantum states of other ions in the ion trap except the first ion. Thus, the crosstalk between the first ion and other ions is small, and the fidelity and accuracy of ion manipulation are high. At the same time, polarization addressing can also be combined with spatial addressing and frequency addressing, and the three act on the ions together, theoretically being able to maximize the addressing performance.

[0147] It should be noted that: when the ion addressing device provided in the above embodiments addresses ions, only the above-mentioned division of each functional module is used for illustration. In practical applications, the above functions can be allocated to different functional modules according to needs, that is, the internal structure of the device is divided into different functional modules to complete all or part of the functions described above. In addition, the ion addressing device provided in the above embodiments and the embodiments of the ion addressing method belong to the same concept, and the specific implementation process is detailed in the method embodiments and will not be elaborated here.

[0148] 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 the form of a computer program product in whole or in part. The computer program product includes one or more computer instructions. When the computer 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 special-purpose computer, a computer network, or other programmable devices. The computer instructions may be stored in a computer-readable storage medium, or transmitted from one computer-readable storage medium to another computer-readable storage medium. For example, the computer instructions may be transmitted from a 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 (DSL)) or a wireless manner (such as infrared, wireless, microwave, etc.). The computer-readable storage medium may be any available medium that can be accessed by a computer, or a data storage device such as a server or data center that includes one or more available media integrated. The available medium may be a magnetic medium (such as a floppy disk, hard disk, magnetic tape), an optical medium (such as a digital versatile disc (DVD)), or a semiconductor medium (such as a solid state disk (SSD)), etc. It should be noted that the computer-readable storage medium mentioned in the embodiments of the present application may be a non-volatile storage medium, that is to say, it may be a non-transitory storage medium.

[0149] It should be understood that the "at least one" mentioned herein refers to one or more, and "multiple" refers to two or more. In the description of the embodiments of the present application, unless otherwise specified, " / " means "or". For example, A / B may mean A or B; the "and / or" herein is merely a description of the association relationship of associated objects, indicating that there can be three relationships. For example, A and / or B may mean: A exists alone, A and B exist simultaneously, and B exists alone. In addition, in order to clearly describe the technical solutions of the embodiments of the present application, in the embodiments of the present application, terms such as "first" and "second" are used to distinguish the same items or similar items with basically the same functions and effects. Those skilled in the art can understand that the terms "first", "second", etc. do not limit the quantity and execution order, and the terms "first", "second", etc. do not necessarily mean different.

[0150] It should be noted that the information (including but not limited to user device information, user personal information, etc.), data (including but not limited to data for analysis, stored data, displayed data, etc.), and signals involved in the embodiments of this application are all authorized by the user or fully authorized by all parties, and the collection, use, and processing of relevant data need to comply with the relevant laws, regulations, and standards of relevant countries and regions.

[0151] The above are the embodiments provided by this application, which are not intended to limit this application. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of this application shall be included within the protection scope of this application.

Claims

1. An ion addressing method, characterized in that: The method comprises: generating a first vortex laser beam, wherein polarized light at different positions in the first vortex laser beam is different, and the different polarized light has different effects on ions; The first vortex laser beam is irradiated onto the ion trap to manipulate a first ion in the ion trap using the first vortex laser beam, wherein the first ion is located at a first position in the first vortex laser beam, and polarized light of the first vortex laser beam at the first position can change the quantum state of the first ion, but the first vortex laser beam does not affect the quantum states of other ions in the ion trap except the first ion.

2. The method according to claim 1, wherein The second ion in the ion trap is adjacent to the first ion, and the second ion is located at a second position in the first vortex laser beam. The first position is the position in the first vortex laser beam where the intensity of ion transition is the highest, and the second position is the position in the first vortex laser beam where the intensity of ion transition is the lowest.

3. The method according to claim 2, wherein The first position and the second position are both located within a first cross section of the first vortex laser beam.

4. The method according to any one of claims 1 to 3, wherein The ions in the ion trap are in a magnetic field with a magnetic field gradient, and the magnetic field gradient causes differences in transition frequencies of multiple ions in the ion trap. The first vortex laser beam can also cause the first ion to undergo energy level transition, but other ions in the ion trap except the first ion do not undergo energy level transition.

5. The method according to any one of claims 1 to 4, characterized in that Before generating the first vortex laser beam, the method further includes: Tuning the laser parameters to be tested using the test beam, determining the tuned laser parameters as vortex laser parameters, wherein the vortex laser beam generated according to the tuned laser parameters is capable of causing a crosstalk magnitude between the ion to be manipulated and adjacent ions of the ion to be manipulated to be less than a first threshold; The generating of the first vortex laser beam comprises: The first vortex laser beam is generated according to the vortex laser parameters.

6. The method according to claim 5, wherein The test beam includes a first Gaussian laser beam and a second vortex laser beam, the laser parameters to be tested include a first laser parameter to be tested and a second laser parameter to be tested, and the vortex laser parameters include a tuned first laser parameter and a tuned second laser parameter; The method of using the test beam to tune the laser parameters to be tested and determining the tuned laser parameters as vortex laser parameters includes: generating the first Gaussian laser beam according to the first laser parameter to be tested, and tuning the first laser parameter to be tested using the first Gaussian laser beam to obtain the tuned first laser parameter, wherein the Gaussian laser beam generated according to the tuned first laser parameter is capable of causing the Rabi frequency of the ion to be manipulated to be higher than a second threshold; The second vortex laser beam is generated according to the tuned first laser parameter and the second laser parameter to be tested, and the second laser parameter to be tested is tuned using the second vortex laser beam to obtain the tuned second laser parameter.

7. The method according to claim 6, wherein Generating the second vortex laser beam according to the tuned first laser parameter and the second laser parameter to be tested, and tuning the second laser parameter to be tested using the second vortex laser beam to obtain the tuned second laser parameter, comprises: generating the second vortex laser beam according to the tuned first laser parameters and the second laser parameters to be tested; irradiating the ion trap with the second vortex laser beam; reading out the quantum state of each ion in the ion trap to obtain the true quantum state of each ion; determining a test result, the test result characterizing a difference between an actual quantum state and an expected quantum state of each ion in the ion trap; If the gap exceeds a third threshold, the second laser parameter to be tested is optimized with the goal of reducing the gap, the optimized second laser parameter is determined as the second laser parameter to be tested, and the step of generating the second vortex laser beam according to the optimized first laser parameter and the second laser parameter to be tested is returned to execution; If the difference does not exceed the third threshold, the second laser parameter after this tuning is determined as the tuned second laser parameter included in the vortex laser parameter.

8. The method according to claim 7, wherein The first laser parameters include beam pointing and / or laser frequency, and the second laser parameters include beam size and / or ion spacing.

9. An ion addressing device, characterized in that: The device comprises: A laser generating module generates a first vortex laser beam, wherein polarized light at different positions in the first vortex laser beam has different effects on ions; A laser transmission module is used to irradiate the first vortex laser beam toward the ion trap to manipulate a first ion in the ion trap using the first vortex laser beam, wherein the first ion is located at a first position in the first vortex laser beam, and polarized light of the first vortex laser beam at the first position can change the quantum state of the first ion, but the first vortex laser beam does not affect the quantum state of other ions in the ion trap except the first ion.

10. The device according to claim 9, wherein The second ion in the ion trap is adjacent to the first ion, and the second ion is located at a second position in the first vortex laser beam. The first position is the position in the first vortex laser beam where the intensity of ion transition is the highest, and the second position is the position in the first vortex laser beam where the intensity of ion transition is the lowest.

11. The device according to claim 10, wherein The first position and the second position are both located within a first cross section of the first vortex laser beam.

12. The device according to any one of claims 9 to 11, characterized in that The ions in the ion trap are in a magnetic field with a magnetic field gradient, and the magnetic field gradient causes differences in transition frequencies of multiple ions in the ion trap. The first vortex laser beam can also cause the first ion to undergo energy level transition, but other ions in the ion trap except the first ion do not undergo energy level transition.

13. The device according to any one of claims 9 to 12, characterized in that The device further comprises: a parameter tuning module, configured to tune the laser parameters to be tested using the test beam, determine the tuned laser parameters as vortex laser parameters, and generate a vortex laser beam according to the tuned laser parameters so that the crosstalk between the ion to be manipulated and its adjacent ions is less than a first threshold; The laser generating module comprises: The first generating submodule is configured to generate the first vortex laser beam according to the vortex laser parameters.

14. The device according to claim 13, wherein The test beam includes a first Gaussian laser beam and a second vortex laser beam, the laser parameters to be tested include a first laser parameter to be tested and a second laser parameter to be tested, and the vortex laser parameters include a tuned first laser parameter and a tuned second laser parameter; The parameter tuning module includes: a first tuning submodule, configured to generate the first Gaussian laser beam according to the first laser parameter to be tested, and tune the first laser parameter to be tested using the first Gaussian laser beam to obtain the tuned first laser parameter, wherein the Gaussian laser beam generated according to the tuned first laser parameter is capable of causing the Rabi frequency of the ion to be manipulated to be higher than a second threshold; The second tuning submodule is used to generate the second vortex laser beam according to the tuned first laser parameters and the second laser parameters to be tested, and use the second vortex laser beam to tune the second laser parameters to be tested to obtain the tuned second laser parameters.

15. The device according to claim 14, wherein The second tuning submodule is specifically used for: generating the second vortex laser beam according to the tuned first laser parameters and the second laser parameters to be tested; irradiating the ion trap with the second vortex laser beam; reading out the quantum state of each ion in the ion trap to obtain the true quantum state of each ion; determining a test result, the test result characterizing a difference between an actual quantum state and an expected quantum state of each ion in the ion trap; If the gap exceeds a third threshold, the second laser parameter to be tested is optimized with the goal of reducing the gap, the optimized second laser parameter is determined as the second laser parameter to be tested, and the step of generating the second vortex laser beam according to the optimized first laser parameter and the second laser parameter to be tested is returned to execution; If the difference does not exceed the third threshold, the second laser parameter after this tuning is determined as the tuned second laser parameter included in the vortex laser parameter.

16. The device according to claim 15, characterized in that The first laser parameters include beam pointing and / or laser frequency, and the second laser parameters include beam size and / or ion spacing.

17. An ion addressing system, characterized in that: The system comprises an ion trap and an ion addressing device, wherein the ion trap contains a plurality of ions; the ion addressing device is used to implement the method according to any one of claims 1 to 8.

18. A computer-readable storage medium, characterized in that The storage medium stores a computer program, which, when executed by a processor, implements the steps of the method according to any one of claims 1 to 8.

19. A computer program product, characterized in that The computer program product stores computer instructions, and when the computer instructions are executed by a processor, the steps of the method according to any one of claims 1 to 8 are implemented.

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