Method and device for synchronous two-atom resonance excitation based on optical lattice cold atomic system

Abstract

This application discloses a method and apparatus for synchronous resonant excitation of two atoms in an optical lattice cold atom system, applicable to a dual-potential-well system. Each of the two potential wells in the dual-potential-well system contains one cold atom, and the two cold atoms are in the same orbit in different potential wells before and after a transition. The method includes: determining the wavefunction expansions of the initial state and target state of the two cold atoms under Wannier basis vectors, where the initial state and target state correspond to the two cold atoms being in the same orbit in different potential wells before and after a transition, respectively; determining the energy difference between the initial state and the target state based on the wavefunction expansion; determining the excitation field based on the energy difference, the selected wavelength, and the oscillation intensity; and applying the excitation field to the dual-potential-well system to cause the two cold atoms to transition from the initial state to the target state. Using this application embodiment facilitates the realization of synchronous resonant excitation of two atoms, thereby providing a theoretical basis for the physical realization of quantum computing based on an optical lattice cold atom system.

Description

Technical Field

[0001] This invention relates to the field of quantum computing technology, and in particular to a method and apparatus for synchronous resonant excitation of two atoms in an optical lattice cold atom system. Background Technology

[0002] Quantum computing based on optical lattice cold atom systems is one of the most promising physical implementation schemes for quantum computing. It utilizes periodic potential wells formed by lasers to trap ultracold neutral atoms, and uses the internal states of the atoms as qubits, achieving quantum logic gates and many-body entanglement through precise laser manipulation. This platform has significant advantages in scalability, coherence time, and parallel operation capabilities.

[0003] In quantum computing based on optical lattice cold atom systems, diatomic synchronous resonant excitation is the core mechanism for achieving high-fidelity, fast two-qubit gates (such as CNOT gates and CZ gates). Therefore, how to achieve diatomic synchronous resonant excitation is a prerequisite for the physical realization of quantum computing based on optical lattice cold atom systems. Summary of the Invention

[0004] This application provides a method and apparatus for biatomic synchronous resonance excitation in an optical lattice cold atom system, which is beneficial for realizing biatomic synchronous resonance excitation and thus provides a theoretical basis for the physical realization of quantum computing based on an optical lattice cold atom system.

[0005] The first aspect of this application provides a method for synchronous resonance excitation of two atoms in a dual-potential-well system based on an optical lattice cold atom system. This method is applied to a dual-potential-well system, where each of the two potential wells contains one cold atom. The two cold atoms are in the same orbital within different potential wells before and after a transition. The method includes:

[0006] The wavefunction expansions of the initial states and target states of the two cold atoms under the Wannier basis vectors are determined. The initial states correspond to the same orbits in different potential wells before the two cold atoms transition, and the target states correspond to the same orbits in different potential wells after the two cold atoms transition. The energy difference between the initial state and the target state is determined based on the wavefunction expansion. The excitation field is determined based on the energy difference, the selected wavelength, and the oscillation intensity. The excitation field is applied to the double potential well system so that the two cold atoms transition from the initial state to the target state.

[0007] Optionally, the excitation field is described by an excitation function, which is: , in, The selected oscillation intensity, The vibration frequency, , The energy difference between the initial state and the target state is... To generate the wave vector of the field, The selected laser wavelength, and These refer to the excitation spatial location and excitation time, respectively.

[0008] Optionally, after applying the excitation field to the double potential well system to cause the two cold atoms to transition from the initial state to the target state, the method further includes: Measure the fidelity of the initial state and / or the target state; When the fidelity of the initial state no longer decreases, and / or the fidelity of the target state no longer increases, the excitation field is turned off and the value of the excitation time is determined.

[0009] Optionally, the target state includes a first target state and a second target state, wherein the second target state is higher than the first target state, and before determining the excitation field based on the energy difference and the selected wavelength and oscillation intensity, the method further includes: Based on the correspondence between the excitation time and the oscillation intensity, the oscillation intensity when the excitation time is the same is selected as the oscillation intensity for the transition from the initial state to the first target state and the oscillation intensity for the transition from the first target state to the second target state.

[0010] The second aspect of this application provides a dual-atom synchronous resonance excitation device based on an optical lattice cold atom system, applied to a dual-potential-well system. Each of the two potential wells in the dual-potential-well system contains one cold atom, and both cold atoms are in the same orbit in different potential wells before and after a transition. The device includes: The wave function determination unit is used to determine the wave function expansion of the initial state and the target state of the two cold atoms under the Wannier basis vectors. The initial state corresponds to the same orbit of the two cold atoms in different potential wells before the transition, and the target state corresponds to the same orbit of the two cold atoms in different potential wells after the transition. An energy difference determination unit is used to determine the energy difference between the initial state and the target state based on the wave function expansion. An excitation field determination unit is used to determine the excitation field based on the energy difference, the selected wavelength, and the oscillation intensity. An excitation unit is used to apply the excitation field to the double potential well system so that the two cold atoms transition from the initial state to the target state.

[0011] Optionally, the excitation field is described by an excitation function, which is: , in, The selected oscillation intensity, The vibration frequency, , The energy difference between the initial state and the target state is... To generate the wave vector of the field, The selected laser wavelength, and These refer to the excitation spatial location and excitation time, respectively.

[0012] Optionally, after applying the excitation field to the double potential well system to cause the two cold atoms to transition from the initial state to the target state, the device further includes: A fidelity measurement unit is used to measure the fidelity of the initial state and / or the target state; The excitation unit is further configured to turn off the excitation field when the fidelity of the initial state no longer decreases and / or the fidelity of the target state no longer increases. An excitation time determination unit is used to determine the value of the excitation time.

[0013] Optionally, the target state includes a first target state and a second target state, wherein the second target state is higher than the first target state, and before determining the excitation field based on the energy difference and the selected wavelength and oscillation intensity, the device further includes: The oscillation intensity determination unit is used to select the oscillation intensity when the excitation time is the same as the oscillation intensity when the excitation time is the same, based on the correspondence between the excitation time and the oscillation intensity.

[0014] A third aspect of this application provides an electronic device, including: a processor and a memory; The processor is connected to a memory, wherein the memory is used to store computer programs and the processor is used to invoke the computer programs to execute the methods as described in the first aspect of the embodiments of this application.

[0015] A fourth aspect of this application provides a computer-readable storage medium storing a computer program, the computer program including program instructions, which, when executed by a processor, perform the method as described in the first aspect of this application.

[0016] This application provides a method and apparatus for synchronous resonant excitation of two atoms in an optical lattice cold atom system, applicable to a dual-potential-well system. Each of the two potential wells in the dual-potential-well system contains one cold atom, and the two cold atoms are in the same orbit in different potential wells before and after a transition. The method includes: determining the wavefunction expansions of the initial state and the target state of the two cold atoms under Wannier basis vectors, where the initial state corresponds to the two cold atoms being in the same orbit in different potential wells before the transition, and the target state corresponds to the two cold atoms being in the same orbit in different potential wells after the transition; determining the energy difference between the initial state and the target state based on the wavefunction expansion; determining the excitation field based on the energy difference, the selected wavelength, and the oscillation intensity; and applying the excitation field to the dual-potential-well system to cause the two cold atoms to transition from the initial state to the target state. The dynamic process in this embodiment is a first-order process, not a traditional higher-order transition process, and can directly transition from the initial state to the target state without any intermediate processes. Using this embodiment facilitates the realization of synchronous resonant excitation of two atoms, thereby providing a theoretical basis for the physical realization of quantum computing based on optical lattice cold atom systems. Attached Figure Description

[0017] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0018] Figure 1 An example system block diagram of a dual potential well system of one-dimensional optical lattice cold atoms provided in one embodiment of this application is shown; Figure 2 A flowchart illustrating a method for simultaneous resonant excitation of two atoms in an optical lattice cold atom system according to an embodiment of this application is shown. Figure 3 The following is an example of the optical lattice double potential well energy spectrum under different interactions provided in one embodiment of this application; Figure 4 An embodiment of this application is shown. The dynamic evolution diagram.

[0019] Figure 5 An embodiment of this application is shown. The dynamic evolution diagram.

[0020] Figure 6 An embodiment of this application is shown. Gradually stimulated and The dynamic evolution diagram; Figure 7This paper shows a schematic diagram of the structure of a dual-atom synchronous resonance excitation device based on an optical lattice cold atom system according to an embodiment of this application; Figure 8 A schematic diagram of the structure of a computer device provided in one embodiment of this application is shown. Detailed Implementation

[0021] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of this application.

[0022] Classical computers use transistors to encode information in binary data, such as bits, where each bit can represent a value of 1 or 0. These 1s and 0s act as switches to drive the functions of a classical computer. If there are n bits of data, there are 2^n possible classical states, and one state is represented at a time.

[0023] Quantum computers use quantum processors that operate on data represented by qubits, also known as quantum bits. A single qubit can represent the classical binary states "0" or "1", or a superposition of "0" and "1". Because it can represent a superposition of "0" and "1", a qubit can represent both "0" and "1" states simultaneously. For example, if there are n bits of data, then... A quantum state can be represented simultaneously. Furthermore, qubits in a superposition can be correlated with each other, a phenomenon known as entanglement, where the state of one qubit (whether 1, 0, or both) depends on the state of another qubit, and more information can be encoded within two entangled qubits. Based on the principles of superposition and entanglement, qubits enable quantum computers to perform functions that might be relatively complex and time-consuming for classical computers.

[0024] Cold atom lattice systems are the core experimental platform for ultracold atom physics and quantum simulation. By using laser beams to construct periodic "optical lattices" in a vacuum, ultracold atoms (such as bosons 87Rb, 6Li, etc.) are trapped in artificially designed lattice sites, thereby simulating the behavior of strongly correlated quantum materials in condensed matter physics.

[0025] Please refer to Figure 1 This illustration shows an example system block diagram of a one-dimensional optical lattice cold atom dual-potential-well system according to an embodiment of this application. In this dual-potential-well system, each of the two potential wells contains one cold atom, and both cold atoms are in the same orbit in different potential wells before and after the transition. The Hamiltonian of the system is: , in, atomic mass Let i be the position of the i-th atom within the potential well. Let be the potential well depth, and g be the interatomic interaction strength.

[0026] Please refer to Figure 2 This illustration shows a flowchart of a method for simultaneous resonant excitation of two atoms in an optical lattice cold atom system according to an embodiment of this application. This method can be applied to processing... Figure 1 In the computer device depicting the dual-potential-well system, the aforementioned computer device refers to an electronic device capable of data computation and processing. The method may include the following steps: Step 201: Determine the wave function expansion of the initial state and the target state of the two cold atoms under the Wannier basis vectors. The initial state corresponds to the same orbit of the two cold atoms in different potential wells before the transition, and the target state corresponds to the same orbit of the two cold atoms in different potential wells after the transition.

[0027] The Wannier basis vectors are crucial localized real-space basis functions in solid-state physics and quantum many-body theory, used to describe electronic states in crystals. They form a Fourier transform pair with the Bloch wave function and are widely applied in band theory, tight-binding models, polarization theory, and topological states of matter. The wave function expansions of the initial and target states using the Wannier basis vectors are as follows: , , in, and Let these represent the wavefunction expansions of the initial and target states of the system in Wannier basis vectors, respectively. and Let these represent the expansion coefficients of the initial state and the target state under the Wannier basis, respectively. and For Wannier basis vector orbitals.

[0028] The theoretical operational mechanism of the two-photon target state can be described as follows: , in, In order to execute the global excitation excitation function, the excitation field is described by the excitation function, which is defined as: , in, The selected oscillation intensity, The vibration frequency, , The energy difference between the initial state and the target state is... To generate the wave vector of the field, The selected laser wavelength, and These refer to the excitation spatial location and excitation time, respectively.

[0029] Step 202: Determine the energy difference between the initial state and the target state based on the wave function expansion.

[0030] Once the wavefunction expansion is determined, it can be applied according to the Hamiltonian equation. Determine the energies corresponding to different wave functions. If the energy corresponding to the initial state is... The energy corresponding to the target state is The energy difference between the two is .

[0031] Step 203: Determine the excitation field based on the energy difference and the selected wavelength and oscillation intensity.

[0032] Step 204: Apply the excitation field to the double potential well system so that the two cold atoms transition from the initial state to the target state.

[0033] Among them, in energy difference Once determined, it can be based on The vibration frequency can be determined. The value of . When the vibration frequency excited by the lattice oscillation. By precisely compensating for the energy level difference between the two initial states and the target quantum state, and then selecting a laser wavelength and a specific oscillation intensity, the specific form of the excitation function can be determined. Applying the excitation field described by this excitation function to the double potential well system allows two cold atoms to transition from the initial state to the target state.

[0034] It should be noted that the transition here can be an upward transition or a downward transition (i.e., radiation). This application uses upward transition as an example. For downward radiation, refer to the example of upward transition, and it will not be elaborated further.

[0035] It should also be noted that the wavelength and oscillation intensity of the laser can take any value, and are not limited here.

[0036] For example, let's define the initial state as two atoms in s orbitals of different potential wells, and the higher-dimensional target states as two atoms in p orbitals and d orbitals of different potential wells, respectively. Initial state of the system: High-dimensional target state: , Here, L and R represent the atoms in the left and right potential wells, respectively. The optical lattice cold atom system theoretically possesses a sufficient number of energy levels; however, to verify the diatomic excitation mechanism, only two target states are selected for verification. For example... Figure 3 As shown, this illustrates the optical lattice double potential well energy spectrum under different interactions according to an embodiment of this application. The curves represent the relationship between the eigenenergy of different eigenstates and the magnitude of the interaction. The three curves above represent, from bottom to top, the following relationships: , , .

[0037] Step 1: Place the atoms in s orbitals of different potential wells, and then apply a periodic driving field to make the atoms move from... Simultaneously jump to The specific activation function is: , in for as well as The oscillation frequency corresponding to the energy level difference between orbitals The intensity of the oscillation during this phase Step 2: Let the atoms... Leap to The specific excitation function is , in for as well as The oscillation frequency corresponding to the energy level difference between orbitals, and the oscillation intensity of A2 in this stage.

[0038] The above example uses embodiments of this application to remove diatoms from the system. Reliable excitation Further from Stimulated .

[0039] It should be noted that the dynamic process in this embodiment is a first-order process, not a traditional higher-order transition process. It can directly transition from the initial state to the target state without any intermediate processes. Assume the initial state is... The target state is You can directly from Leap to No need to go through the process first Leap to , and then from Leap to The intermediate process; nor is it necessary to go through the process of first starting from Leap to , and then from Leap to The intermediate processes. Of course, other intermediate processes may also be included, which will not be listed in detail here.

[0040] This application provides a method and apparatus for synchronous resonant excitation of two atoms in an optical lattice cold atom system, applicable to a dual-potential-well system. Each of the two potential wells in the dual-potential-well system contains one cold atom, and the two cold atoms are in the same orbit in different potential wells before and after a transition. The method includes: determining the wavefunction expansions of the initial state and the target state of the two cold atoms under Wannier basis vectors, where the initial state corresponds to the two cold atoms being in the same orbit in different potential wells before the transition, and the target state corresponds to the two cold atoms being in the same orbit in different potential wells after the transition; determining the energy difference between the initial state and the target state based on the wavefunction expansion; determining the excitation field based on the energy difference, the selected wavelength, and the oscillation intensity; and applying the excitation field to the dual-potential-well system to cause the two cold atoms to transition from the initial state to the target state. The dynamic process in this embodiment is a first-order process, not a traditional higher-order transition process, and can directly transition from the initial state to the target state without any intermediate processes. Using this embodiment facilitates the realization of synchronous resonant excitation of two atoms, thereby providing a theoretical basis for the physical realization of quantum computing based on optical lattice cold atom systems.

[0041] In the above embodiments, two cold atoms are transitioned from the initial state to the target state only through an excitation field. However, the exact timing of shutting off the excitation field, i.e., the duration of the excitation field application—the excitation duration—is not specified. Therefore, this application provides the following embodiments.

[0042] In one embodiment provided in this application, after applying the excitation field to the double potential well system to cause the two cold atoms to transition from the initial state to the target state, the method further includes: Measure the fidelity of the initial state and / or the target state; When the fidelity of the initial state no longer decreases, and / or the fidelity of the target state no longer increases, the excitation field is turned off and the value of the excitation time is determined.

[0043] Before excitation, the initial state occupies the majority of the system, resulting in a high fidelity close to 1. However, due to the presence of noisy states, this fidelity is often less than 1 in reality. The target state is almost non-existent in the system, thus the fidelity is close to 0. After excitation, the target state occupies the majority of the system, resulting in a high fidelity close to 1. However, due to the presence of noisy states, this fidelity is often less than 1 in reality. The initial state is almost non-existent in the system, thus the fidelity is close to 0. Therefore, by measuring at least one of these two parameters, we can determine whether a complete transition from the initial state to the target state has occurred, thereby determining the time required for complete excitation and, consequently, when to shut down the excitation field.

[0044] For example, we will still select two target states for verification. Please refer to [reference needed]. Figures 4 to 6 Each of these embodiments illustrates a provision provided by this application. , , Gradually stimulated and The dynamic evolution diagram.

[0045] like Figure 4 As shown, the system starts from the initial state. Gradually moving towards the first target state Evolution. We apply dithering to the lattice over a finite time period. When the fidelity of the first target state in the system reaches its maximum, this indicates that the system evolves from the initial state. It has evolved into the first objective state. The fidelity of the first target state is approximately 99.6%, and even when the excitation field of the lattice system is turned off, the system can still be stored well in the first target state.

[0046] Building upon this, we proceed with the evolution of the second objective state. For Figure 5 In other words, the system consists of a first objective state. Towards the second target state Evolution. The second target state has a fidelity of approximately 99.9% in the system. When the excitation field of the lattice system is turned off, the system can still be well stored in the second target state.

[0047] To verify the scalability of diatomic excitations, we placed the system in its initial state. Let it first move towards the first target state. Excitation, followed by a period of time, then transition to the second target state. The evolution proceeds. The specific dynamic evolution diagram is as follows: Figure 6 As shown in the figure. It can be observed from the figure that the initial state at the initial moment... The fidelity is close to 1, while the first target state Second target state The fidelity is almost zero, consistent with the initial conditions. As evolution progresses, the initial state... The fidelity drops rapidly, while the first target state The fidelity rises rapidly and reaches a peak, indicating that the system transitions from the initial state. Effective transition to the first target state Subsequently, the first target state Fidelity begins to decrease, while the second target state... The fidelity gradually increases and tends to stabilize, eventually reaching a high fidelity of 99.9%. This indicates that by controlling the excitation timing, the system can transition stepwise from the initial low target state to the high target state, and the fidelity of each target state exhibits regular oscillations throughout the evolution process, which is consistent with theoretical expectations.

[0048] In summary, the diatomic excitation mechanism can prepare high-fidelity target states within a finite time, and these prepared target states can be well stored in the system, indicating that the prepared target states have excellent decoherence capabilities. The diatomic excitation mechanism allows the system to be directly excited from the initial state to the desired target state, improving preparation efficiency while reducing interference from other states. This demonstrates the feasibility and high efficiency of achieving interatomic transitions through diatomic excitation.

[0049] In the above embodiments, when there are two or more target states, since the energy difference between different orbital energy levels is not constant, the system changes from the initial state. Gradually moving towards the first target state The evolution time and the system from the first objective state Towards the second target state The evolution times are not the same. In engineering applications, if the excitation times can be made consistent, the two gates can be completed synchronously, while suppressing errors caused by parameter fluctuations.

[0050] Suppressing errors caused by parameter fluctuations: Laser power drift, Doppler frequency shift caused by atomic temperature, lattice depth fluctuations, etc. can all cause changes in excitation intensity. If a fixed time pulse is used, these fluctuations are directly converted into excitation probability errors.

[0051] Therefore, in view of the above advantages, in one embodiment provided by this application, the target state includes a first target state and a second target state, wherein the second target state is higher than the first target state, and before determining the excitation field based on the energy difference and the selected wavelength and oscillation intensity, the method further includes: Based on the correspondence between the excitation time and the oscillation intensity, the oscillation intensity when the excitation time is the same is selected as the oscillation intensity for the transition from the initial state to the first target state and the oscillation intensity for the transition from the first target state to the second target state.

[0052] In this embodiment, the oscillation intensity is adjusted. The size of the parameter can be adjusted to allow different target states to be completed at the same excitation time, enabling the dual gates to complete synchronously while suppressing errors caused by parameter fluctuations.

[0053] Figure 7A schematic diagram of a dual-atom synchronous resonance excitation device based on an optical lattice cold atom system according to an embodiment of this application is shown. Applied to a dual-potential-well system, each of the two potential wells in the dual-potential-well system contains a cold atom. Before and after the transition, both cold atoms are in the same orbit in different potential wells. The device includes: The wave function determination unit 701 is used to determine the wave function expansion of the initial state and the target state of the two cold atoms under the Wannier basis vectors. The initial state corresponds to the same orbit of the two cold atoms in different potential wells before the transition, and the target state corresponds to the same orbit of the two cold atoms in different potential wells after the transition. The energy difference determination unit 702 is used to determine the energy difference between the initial state and the target state based on the wave function expansion. Excitation field determination unit 703 is used to determine the excitation field based on the energy difference and the selected wavelength and oscillation intensity; Excitation unit 704 is used to apply the excitation field to the double potential well system so that the two cold atoms transition from the initial state to the target state.

[0054] The excitation field is described by an excitation function, which is: , in, The selected oscillation intensity, The vibration frequency, , The energy difference between the initial state and the target state is... To generate the wave vector of the field, The selected laser wavelength, and These refer to the excitation spatial location and excitation time, respectively.

[0055] Furthermore, still refer to Figure 7 After applying the excitation field to the double potential well system to cause the two cold atoms to transition from the initial state to the target state, the device further includes: The fidelity measurement unit 705 is used to measure the fidelity of the initial state and / or the target state; The excitation unit 704 is further configured to turn off the excitation field when the fidelity of the initial state no longer decreases and / or the fidelity of the target state no longer increases. The excitation time determination unit 706 is used to determine the value of the excitation time.

[0056] Furthermore, still refer to Figure 7The target state includes a first target state and a second target state, wherein the second target state is higher than the first target state. Before determining the excitation field based on the energy difference and the selected wavelength and oscillation intensity, the device further includes: The oscillation intensity determination unit 707 is used to select the oscillation intensity when the excitation time is the same as the oscillation intensity when the excitation time is the same, based on the correspondence between the excitation time and the oscillation intensity.

[0057] Figure 8 A schematic diagram of the structure of a computer device provided in one embodiment of this application is shown, including a memory and a processor. The memory stores a computer program, and when the processor executes the computer program, it implements the functions of the computer system based on the diatomic synchronous resonance excitation method in the optical lattice cold atom system in any of the above embodiments.

[0058] This application also provides a computer-readable storage medium storing a computer program thereon, which, when executed by a computer, causes the computer to perform the functions of the computer system based on the diatomic synchronous resonance excitation method in the optical lattice cold atom system in any of the above embodiments.

[0059] This application also provides a computer program product containing instructions that, when executed by a computer, cause the computer to perform the functions of the computer system based on the diatomic synchronous resonance excitation method in the optical lattice cold atom system described in any of the above embodiments.

[0060] It is understood that the specific examples in this application are only intended to help those skilled in the art better understand the implementation methods of this application, and are not intended to limit the scope of the invention.

[0061] It is understood that in the various embodiments of this application, the sequence number of each process does not imply the order of execution. The execution order of each process should be determined by its function and internal logic, and should not limit the implementation process of the embodiments of this application in any way.

[0062] It is understood that the various implementation methods described in this application can be implemented individually or in combination, and the implementation methods in this application are not limited in this respect.

[0063] Unless otherwise stated, all technical and scientific terms used in the embodiments of this application have the same meaning as commonly understood by one of ordinary skill in the art. The terminology used in this application is for the purpose of describing particular embodiments only and is not intended to limit the scope of this application. The term "and / or" as used in this application includes any and all combinations of one or more of the associated listed items. The singular forms "a," "the," and "the" as used in the embodiments of this application and the appended claims are also intended to include the plural forms unless the context clearly indicates otherwise.

[0064] It is understood that the processor in the embodiments of this application can be an integrated circuit chip with signal processing capabilities. During implementation, each step of the above method embodiments can be completed by the integrated logic circuits in the processor's hardware or by instructions in software form. The processor can be a general-purpose processor, a digital signal processor (DSP), an application-specific integrated circuit (ASIC), a field-programmable gate array (FPGA), or other programmable logic devices, discrete gate or transistor logic devices, or discrete hardware components. It can implement or execute the methods, steps, and logic block diagrams disclosed in the embodiments of this application. The general-purpose processor can be a microprocessor or any conventional processor. The steps of the methods disclosed in the embodiments of this application can be directly embodied in the execution of a hardware decoding processor, or executed by a combination of hardware and software modules in the decoding processor. The software modules can be located in random access memory, flash memory, read-only memory, programmable read-only memory, electrically erasable programmable memory, registers, or other mature storage media in the art. This storage medium is located in memory; the processor reads information from the memory and, in conjunction with its hardware, completes the steps of the above method.

[0065] It is understood that the memory in the embodiments of this application may be volatile memory or non-volatile memory, or may include both volatile and non-volatile memory. Specifically, non-volatile memory may be read-only memory (ROM), programmable read-only memory (PROM), erasable programmable read-only memory (EPROM), electrically erasable programmable read-only memory (EEPROM), or flash memory. Volatile memory may be random access memory (RAM). It should be noted that the memory in the systems and methods described herein is intended to include, but is not limited to, these and any other suitable types of memory.

[0066] Those skilled in the art will recognize that the units and algorithm steps of the various examples described in conjunction with the embodiments disclosed herein can be implemented in electronic hardware, or a combination of computer software and electronic hardware. Whether these functions are implemented in hardware or software depends on the specific application and design constraints of the technical solution. Those skilled in the art can use different methods to implement the described functions for each specific application, but such implementation should not be considered beyond the scope of this application.

[0067] Those skilled in the art will clearly understand that, for the sake of convenience and brevity, the specific working processes of the systems, devices, and units described above can be referred to the corresponding processes in the aforementioned method implementations, and will not be repeated here.

[0068] In the several embodiments provided in this application, it should be understood that the disclosed systems, apparatuses, and methods can be implemented in other ways. For example, the apparatus embodiments described above are merely illustrative; for instance, the division of units is only a logical functional division, and in actual implementation, there may be other division methods. For example, multiple units or components may be combined or integrated into another system, or some features may be ignored or not executed. Furthermore, the mutual coupling or direct coupling or communication connection shown or discussed may be through some interfaces; the indirect coupling or communication connection between apparatuses or units may be electrical, mechanical, or other forms.

[0069] The units described as separate components may or may not be physically separate. The components shown as units may or may not be physical units; that is, they may be located in one place or distributed across multiple network units. Some or all of the units can be selected to achieve the purpose of this embodiment, depending on actual needs.

[0070] In addition, the functional units in the various embodiments of this application can be integrated into one processing unit, or each unit can exist physically separately, or two or more units can be integrated into one unit.

[0071] If a function is implemented as a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of this application, in essence, or the part that contributes to the prior art, or part of the technical solution, can be embodied in the form of a software product. The computer software product is stored in a storage medium and includes several instructions to cause a computer device (which may be a personal computer, server, or network device, etc.) to execute all or part of the steps of the methods of various embodiments of this application. The aforementioned storage medium includes various media capable of storing program code, such as USB flash drives, portable hard drives, read-only memory (ROM), random access memory (RAM), magnetic disks, or optical disks.

[0072] The above are merely specific embodiments of this application, but the scope of protection of this invention is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in this application should be included within the scope of protection of this application. Therefore, the scope of protection of this invention should be determined by the scope of the claims.

Claims

1. A method for synchronous resonance excitation of two atoms in an optical lattice cold atom system, characterized in that, The method, applied to a dual-potential-well system, wherein each of the two potential wells contains a cold atom, and the two cold atoms are in the same orbit in different potential wells before and after a transition, includes: The wavefunction expansions of the initial states and target states of the two cold atoms under the Wannier basis vectors are determined. The initial states correspond to the same orbits in different potential wells before the two cold atoms transition, and the target states correspond to the same orbits in different potential wells after the two cold atoms transition. The energy difference between the initial state and the target state is determined based on the wavefunction expansion. The excitation field is determined based on the energy difference, the selected wavelength, and the oscillation intensity. The excitation field is applied to the double potential well system so that the two cold atoms transition from the initial state to the target state.

2. The method according to claim 1, characterized in that, The excitation field is described by an excitation function, which is: ， in, The selected oscillation intensity, The vibration frequency, , The energy difference between the initial state and the target state is... To generate the wave vector of the field, The selected laser wavelength, and These refer to the excitation spatial location and excitation time, respectively.

3. The method according to claim 2, characterized in that, After applying the excitation field to the double potential well system to cause the two cold atoms to transition from the initial state to the target state, the method further includes: Measure the fidelity of the initial state and / or the target state; When the fidelity of the initial state no longer decreases, and / or the fidelity of the target state no longer increases, the excitation field is turned off and the value of the excitation time is determined.

4. The method according to claim 3, characterized in that, The target state includes a first target state and a second target state, wherein the second target state is higher than the first target state. Before determining the excitation field based on the energy difference and the selected wavelength and oscillation intensity, the method further includes: Based on the correspondence between the excitation time and the oscillation intensity, the oscillation intensity when the excitation time is the same is selected as the oscillation intensity for the transition from the initial state to the first target state and the oscillation intensity for the transition from the first target state to the second target state.

5. A dual-atom synchronous resonance excitation device based on an optical lattice cold atom system, characterized in that, An apparatus for use in a dual-potential-well system, wherein each of the two potential wells contains a cold atom, and the two cold atoms are in the same orbit in different potential wells before and after a transition, the apparatus comprising: The wave function determination unit is used to determine the wave function expansion of the initial state and the target state of the two cold atoms under the Wannier basis vectors. The initial state corresponds to the same orbit of the two cold atoms in different potential wells before the transition, and the target state corresponds to the same orbit of the two cold atoms in different potential wells after the transition. An energy difference determination unit is used to determine the energy difference between the initial state and the target state based on the wave function expansion. An excitation field determination unit is used to determine the excitation field based on the energy difference, the selected wavelength, and the oscillation intensity. An excitation unit is used to apply the excitation field to the double potential well system so that the two cold atoms transition from the initial state to the target state.

6. The apparatus according to claim 5, characterized in that, The excitation field is described by an excitation function, which is: ， in, The selected oscillation intensity, The vibration frequency, , The energy difference between the initial state and the target state is... To generate the wave vector of the field, The selected laser wavelength, and These refer to the excitation spatial location and excitation time, respectively.

7. The method according to claim 6, characterized in that, After applying the excitation field to the double potential well system to cause the two cold atoms to transition from the initial state to the target state, the device further includes: A fidelity measurement unit is used to measure the fidelity of the initial state and / or the target state; The excitation unit is further configured to turn off the excitation field when the fidelity of the initial state no longer decreases and / or the fidelity of the target state no longer increases. An excitation time determination unit is used to determine the value of the excitation time.

8. The apparatus according to claim 7, characterized in that, The target state includes a first target state and a second target state, wherein the second target state is higher than the first target state. Before determining the excitation field based on the energy difference and the selected wavelength and oscillation intensity, the device further includes: The oscillation intensity determination unit is used to select the oscillation intensity when the excitation time is the same as the oscillation intensity when the excitation time is the same, based on the correspondence between the excitation time and the oscillation intensity.

9. An electronic device, characterized in that, include: Processor and memory; The processor is connected to a memory, wherein the memory is used to store a computer program, and the processor is used to invoke the computer program to perform the method as described in any one of claims 1-4.

10. A computer-readable storage medium, characterized in that, The computer-readable storage medium stores a computer program, the computer program including program instructions that, when executed by a processor, perform the method as described in any one of claims 1-4.

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