Laser positioning method and electronic equipment based on optical tweezers

Abstract

The present invention provides a laser positioning method and electronic device based on optical tweezers, comprising: obtaining the Rydberg resonance frequencies of at least two atoms captured by a first optical tweezer based on at least two laser powers of a target laser; determining a first single-photon Rabi frequency of the atoms captured by the first optical tweezers and a first laser power corresponding to the first single-photon Rabi frequency based on the at least two laser powers and the at least two Rydberg resonance frequencies; obtaining a second single-photon Rabi frequency of the atoms captured by a second optical tweezers when the target laser is at the first laser power; and determining the relative position of the target laser spot relative to the first and second optical tweezers based on the first and second single-photon Rabi frequencies. The first single-photon Rabi frequency can be determined based on the quantitative relationship between the laser power and the Rydberg resonance frequency, and the equilibrium position of the optical tweezers can be quickly and accurately determined based on the first and second single-photon Rabi frequencies.

Description

Technical Field

[0001] The present invention relates to the field of quantum computing, and in particular to a laser positioning method and electronic equipment based on optical tweezers. Background Art

[0002] In the field of neutral atom quantum computing, a two-bit gate can be realized based on the Rydberg effect between atoms. This requires that both atoms can be excited to the Rydberg state and the distance between them should be within the Rydberg blockade radius. Therefore, it is necessary to control the single-photon Rabi frequency difference of the Rydberg laser at the two atoms to be as small as possible and the positioning of the two atoms as accurately as possible. Therefore, atoms can be captured by optical tweezers to precisely control their position.

[0003] The current positioning method is to capture images of the relative positions of the excitation light and the optical tweezers using a CCD camera, determine the focus of the excitation light based on the position of the excitation light spot center and the geometric center of the two optical tweezers, and adjust the position of the excitation light so that the excitation light covers the two optical tweezers as evenly as possible, so that the single-photon Rabi frequency difference of the Rydberg laser at the two atoms is as small as possible. The method of obtaining the equilibrium position of the optical tweezers by capturing images with a CCD camera can only be applied when the propagation direction of the excitation light and the optical tweezers is the same, and is not applicable when the directions are opposite. In addition, there is a certain deviation between the spot position captured by the CCD camera and the actual spot position, and the balance of the geometric position cannot accurately determine whether the light intensity at the atom is balanced. Therefore, it is inaccurate to determine the equilibrium position between the optical tweezers by the geometric center between the spots. In summary, the method of obtaining the equilibrium position of the optical tweezers by capturing images with a CCD camera has limited application scenarios, large errors in positioning the equilibrium position, poor accuracy, and low practicality. Summary of the Invention

[0004] The present invention provides a laser positioning method and electronic equipment based on optical tweezers, so as to solve the problems that the method of acquiring the equilibrium position of optical tweezers by collecting data with a CCD camera has limited application scenarios and poor accuracy in positioning the equilibrium position.

[0005] In a first aspect, the present invention provides a laser positioning method based on optical tweezers, comprising:

[0006] acquiring Rydberg resonance frequencies of at least two atoms trapped by the first optical tweezers according to at least two laser powers of the target laser;

[0007] determining a first single-photon Rabi frequency of the atom trapped by the first optical tweezers and a first laser power corresponding to the first single-photon Rabi frequency according to the at least two laser powers and the at least two Rydberg resonance frequencies;

[0008] When the target laser is at the first laser power, obtaining a second single-photon Rabi frequency of the atom trapped by the second optical tweezers;

[0009] The relative position of the target laser spot relative to the first optical tweezers and the second optical tweezers is determined according to the first single-photon Rabi frequency and the second single-photon Rabi frequency.

[0010] Optionally, determining a first single-photon Rabi frequency of an atom trapped by the first optical tweezers and a first laser power corresponding to the first single-photon Rabi frequency based on at least two laser powers and at least two Rydberg resonance frequencies includes:

[0011] Obtaining a proportionality coefficient between the laser power of the target laser and the square of the first single-photon Rabi frequency;

[0012] Determining a first positive correlation between the laser power of the target laser and the Rydberg resonance frequency of the atoms trapped by the first optical tweezers based on at least two of the laser powers and at least two of the Rydberg resonance frequencies;

[0013] According to the proportionality coefficient, a first single-photon Rabi frequency of the atom captured by the first optical tweezers is determined when the target laser is at the first laser power.

[0014] Optionally, determining a first positive correlation between the laser power of the target laser and the Rydberg resonance frequency of the atoms trapped by the first optical tweezers by using at least two laser powers and at least two Rydberg resonance frequencies includes:

[0015] obtaining a second positive correlation between the AC Stark frequency shift and the Rydberg resonance frequency of the atom trapped by the first optical tweezers;

[0016] A first positive correlation between the laser power of the target laser and the Rydberg resonance frequency of the atoms trapped by the first optical tweezers is determined according to the second positive correlation and the proportional coefficient.

[0017] Optionally, obtaining a proportional coefficient between the laser power of the target laser and the square of the first single-photon Rabi frequency includes:

[0018] acquiring a third positive correlation between the laser power of the target laser and the laser intensity at the atom captured by the first optical tweezers;

[0019] acquiring a fourth positive correlation between the laser intensity and the square of the first single-photon Rabi frequency;

[0020] The proportionality coefficient is determined based on the third positive correlation and the fourth positive correlation.

[0021] Optionally, determining a first positive correlation between the laser power of the target laser and the Rydberg resonance frequency of the atoms trapped by the first optical tweezers by using at least two laser powers and at least two Rydberg resonance frequencies includes:

[0022] Determining a single-photon detuning coefficient of an atom trapped by the first optical tweezers based on a first laser frequency of the target laser and a second laser frequency of a reference laser, wherein the reference laser is a laser that is confocal with the target laser and has a constant laser power;

[0023] A fifth positive correlation between the target laser, the AC Stark frequency shift, and the first single-photon Rabi frequency is determined according to the single-photon detuning coefficient.

[0024] Optionally, acquiring the Rydberg resonance frequencies of at least two atoms trapped by the first optical tweezers according to at least two laser powers of the target laser includes:

[0025] When the laser power of the target laser remains unchanged, adjusting the excitation frequency of the target laser;

[0026] Obtaining, according to the excitation frequency, a retention probability of the atoms captured by the first optical tweezers;

[0027] The excitation frequency corresponding to the minimum retention probability is determined to be the first Rydberg resonance frequency.

[0028] Optionally, before the step of acquiring the Rydberg resonance frequencies of at least two atoms trapped by the first optical tweezers according to the at least two laser powers of the target laser, the method further includes:

[0029] According to the geometric positional relationship among the first optical tweezers, the second optical tweezers, and the light spot of the target laser, the target laser is adjusted so that the light spot of the target laser uniformly covers the first optical tweezers and the second optical tweezers.

[0030] Optionally, determining the relative position of the target laser spot relative to the first optical tweezers and the second optical tweezers according to the first single-photon Rabi frequency and the second single-photon Rabi frequency includes:

[0031] The offset of the spot center of the target laser relative to the geometric center of the first optical tweezers and the second optical tweezers is determined according to the frequency difference between the first single-photon Rabi frequency and the second single-photon Rabi frequency.

[0032] Optionally, the laser positioning method based on optical tweezers further includes:

[0033] When the frequency difference is greater than a preset difference, the target laser is adjusted so that the light spot of the target laser moves toward the direction of the optical tweezers with a smaller single-photon pulling ratio frequency.

[0034] In a second aspect, the present invention further provides an electronic device comprising a memory and a processor, wherein the processor is configured to implement the steps of the laser frequency switching method as described in any one of the first aspects above when executing a computer program stored in the memory.

[0035] From the above technical solution, it can be seen that the present invention provides a laser frequency switching method and electronic device, including: obtaining the Rydberg resonance frequencies of at least two atoms captured by the first optical tweezers according to at least two laser powers of the target laser; determining the first single-photon Rabi frequency of the atoms captured by the first optical tweezers and the first laser power corresponding to the first single-photon Rabi frequency according to the at least two laser powers and the at least two Rydberg resonance frequencies; obtaining the second single-photon Rabi frequency of the atoms captured by the second optical tweezers when the target laser is at the first laser power; and determining the relative position of the target laser spot relative to the first optical tweezers and the second optical tweezers according to the first single-photon Rabi frequency and the second single-photon Rabi frequency. In the embodiment of the present application, the first single-photon Rabi frequency of the atoms captured by the first optical tweezers under the first laser power can be obtained through the quantitative relationship between at least two laser powers of the target laser and the corresponding Rydberg resonance frequencies of at least two atoms captured by the first optical tweezers. The second single-photon Rabi frequency of the atoms captured by the second optical tweezers under the second laser power can be obtained through the same steps. According to the magnitude relationship between the first single-photon Rabi frequency and the second single-photon Rabi frequency, the relative position of the target laser at the current position relative to the equilibrium position of the two optical tweezers can be determined. The equilibrium position of the optical tweezers can be determined quickly and accurately to facilitate the adjustment of the excitation light, thereby improving the positioning efficiency and positioning quality of the excitation light. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] In order to more clearly illustrate the technical solution of the present application, the following is a brief introduction to the drawings required for use in the embodiments. Obviously, for ordinary technicians in this field, other drawings can be obtained based on these drawings without any creative work.

[0037] Figure 1 A schematic flow chart of a laser positioning method based on optical tweezers provided in an embodiment of the present application;

[0038] Figure 2 A schematic diagram of the radial light intensity distribution of a Gaussian spot focused on a target laser in a laser positioning method based on optical tweezers provided in an embodiment of the present application;

[0039] Figure 3A schematic diagram of frequency fitting of the Rydberg resonance frequency of an atom in a laser positioning method based on optical tweezers provided in an embodiment of the present application;

[0040] Figure 4 A schematic diagram of the Rydberg absorption peak distribution of a laser positioning method based on optical tweezers provided in an embodiment of the present application;

[0041] Figure 5-1 A schematic diagram showing a laser positioning method based on optical tweezers provided in an embodiment of the present application, in which the center of the target laser spot is different from the equilibrium position of two optical tweezers;

[0042] Figure 5-2 A schematic diagram showing a laser positioning method based on optical tweezers provided in an embodiment of the present application, in which the center of the target laser spot is the same as the equilibrium position of two optical tweezers;

[0043] Figure 6 A schematic structural diagram of a diatomic Rydberg excitation device provided in an embodiment of the present application;

[0044] Figure 7 A schematic structural diagram of an electronic device provided in an embodiment of the present application. DETAILED DESCRIPTION

[0045] The embodiments will be described in detail below, and examples thereof are shown in the accompanying drawings. When the following description refers to the drawings, unless otherwise indicated, the same numbers in different drawings represent the same or similar elements. The implementation methods described in the following embodiments do not represent all implementation methods consistent with the present application. They are only examples of systems and methods consistent with some aspects of the present application as detailed in the claims. In the several embodiments provided in the embodiments of the present application, it should be understood that the disclosed devices and methods can also be implemented in other ways, and the device embodiments described below are merely exemplary.

[0046] like Figure 1 As shown, the embodiment of the present application provides a laser positioning method based on optical tweezers. Figure 1 A schematic flow chart of a laser positioning method based on optical tweezers provided in an embodiment of the present application, the method comprising:

[0047] Step S110 : acquiring Rydberg resonance frequencies of at least two atoms trapped by the first optical tweezers according to at least two laser powers of the target laser.

[0048] Exemplarily, the target laser is Rydberg excitation light, and the wavelength of the target laser can be 780 nm or 480 nm. The Rydberg resonance frequency of the atoms trapped by the first optical tweezers can be obtained at different laser powers by adjusting the laser power of the target laser.

[0049] Step S120 , determining a first single-photon Rabi frequency of the atom trapped by the first optical tweezers and a first laser power corresponding to the first single-photon Rabi frequency based on the at least two laser powers and the at least two Rydberg resonance frequencies.

[0050] It should be noted that there is a positive correlation between the Rydberg resonance frequency of an atom and the square of the single-photon Rabi frequency, and there is also a positive correlation between the laser power of the target laser and the Rydberg resonance frequency of the atoms captured by the optical tweezers. Therefore, it can be deduced that there is also a positive correlation between the square of the single-photon Rabi frequency and the laser power. Therefore, based on at least two laser powers and at least two Rydberg resonance frequencies, the correlation coefficient between the laser power and the Rydberg resonance frequency can be determined, and further, the first single-photon Rabi frequency and the corresponding first laser power can be determined based on this correlation coefficient.

[0051] Exemplarily, linear fitting can be performed on at least two laser powers and at least two Rydberg resonance frequencies based on the positive correlation between laser power and Rydberg resonance frequency, and based on the result of the above linear fitting, the first single-photon Rabi frequency of the atom captured by the first optical tweezers when the laser power of the target laser is the first laser power can be determined.

[0052] Step S130 : When the target laser is at the first laser power, obtaining a second single-photon Rabi frequency of the atom trapped by the second optical tweezers.

[0053] For example, the second single-photon Rabi frequency of the atom trapped by the second optical tweezers when the target laser is at the first laser power can be determined by the method in step S120.

[0054] Step S140 : determining the relative position of the target laser spot relative to the first optical tweezers and the second optical tweezers according to the first single-photon Rabi frequency and the second single-photon Rabi frequency.

[0055] Exemplarily, the relative position is an equilibrium position where the single-photon Rabi frequencies of atoms in the first optical tweezers and the second optical tweezers are equal when the laser power of the target laser is the first laser power.

[0056] It should be noted that if Figure 2 As shown, Figure 2A schematic diagram of the radial intensity distribution of a Gaussian spot focused on a target laser in a laser positioning method based on optical tweezers provided in an embodiment of the present application. Since the light intensity within the Gaussian spot formed after the target laser is focused is not uniformly distributed, but rather exhibits a nonlinear relationship that is positively correlated with the distance from the center of the spot, the closer the light intensity is to the center of the spot, the greater the intensity is, and the farther the light intensity is from the center of the spot, the smaller the intensity is. Therefore, simply coarsely adjusting the spot position of the target laser based on the geometric center of the two optical tweezers will not achieve the same single-photon Rabi frequency for the atoms in the first and second optical tweezers, and a small position deviation will result in a large difference in single-photon Rabi frequency.

[0057] By using the quantitative relationship between at least two laser powers of the target laser and the corresponding Rydberg resonance frequencies of at least two atoms captured by the first optical tweezers, the first single-photon Rabi frequency of the atoms captured by the first optical tweezers under the first laser power can be obtained, and the second single-photon Rabi frequency of the atoms captured by the second optical tweezers under the second laser power can be obtained through the same steps. According to the magnitude relationship between the first single-photon Rabi frequency and the second single-photon Rabi frequency, the relative position of the target laser at the current position relative to the equilibrium position of the two optical tweezers can be determined. The equilibrium position of the optical tweezers can be determined quickly and accurately, so as to facilitate the adjustment of the excitation light, thereby improving the positioning efficiency and positioning quality of the excitation light.

[0058] According to some embodiments, determining the first single-photon Rabi frequency of the atom trapped by the first optical tweezers and the first laser power corresponding to the first single-photon Rabi frequency based on the at least two laser powers and the at least two Rydberg resonance frequencies includes:

[0059] Obtaining a proportionality coefficient between the laser power of the target laser and the square of the first single-photon Rabi frequency;

[0060] Determining a first positive correlation between the laser power of the target laser and the Rydberg resonance frequency of the atom trapped by the first optical tweezers based on at least two of the laser powers and at least two of the Rydberg resonance frequencies;

[0061] According to the proportional coefficient, the first single-photon Rabi frequency of the atom captured by the first optical tweezers is determined when the target laser is at the first laser power.

[0062] For example, the above-mentioned proportional coefficient may be set to K, where K is a proportional factor and may be obtained by:

[0063]

[0064] Determine the quantitative relationship between the atomic first single-photon Rabi frequency and the laser power of the target laser, where is the square of the single-photon Rabi frequency of the 780 nm first laser at the atom, and P is the laser power of the target laser.

[0065] like Figure 3 As shown, Figure 3 A frequency fitting diagram of the Rydberg resonance frequency of an atom in a laser positioning method based on optical tweezers provided in an embodiment of the present application can be performed by linearly fitting the laser power value and the Rydberg resonance frequency. The horizontal axis in the image represents the laser power of the 780nm target laser, and the vertical axis represents the Rydberg absorption peak of the atom. According to the slope after fitting, the proportional coefficient K can be determined, and the first single-photon Rabi frequency of the atom can be obtained according to formula (1).

[0066] The above method can directly obtain the first single-photon Rabi frequency of the atom captured by the first optical tweezers by obtaining the laser power and corresponding Rydberg resonance frequency of at least two sets of target lasers, thereby reducing the amount of calculation and improving the determination efficiency, thereby improving the practicality and convenience of the laser positioning method.

[0067] According to some embodiments, determining the first positive correlation between the laser power of the target laser and the Rydberg resonance frequency of the atoms trapped by the first optical tweezers using at least two of the laser powers and at least two of the Rydberg resonance frequencies includes:

[0068] obtaining a second positive correlation between the AC Stark frequency shift and the Rydberg resonance frequency of the atom trapped by the first optical tweezers;

[0069] According to the second positive correlation and the proportional coefficient, a first positive correlation between the laser power of the target laser and the Rydberg resonance frequency of the atoms trapped by the first optical tweezers is determined.

[0070] It should be noted that when performing Rydberg excitation on atoms, two laser beams with different wavelengths need to be emitted from opposite directions. The first laser beam that needs to be adjusted is the target laser, and the other laser beam propagating in the opposite direction is the reference laser. The application of two Rydberg excitation beams will cause the atoms in the optical tweezers to undergo an AC Stark frequency shift, which is proportional to the square difference between the single-photon Rabi frequencies of the first and second lasers. The proportional relationship between the AC Stark frequency shift and the square difference between the single-photon Rabi frequencies of the first and second lasers is as follows:

[0071]

[0072] Among them, δ AC is the AC Stark frequency shift caused by the first laser and the second laser, is the square of the single-photon Rabi frequency of the second 480nm laser at the atom, and A is the proportional coefficient of the AC Stark frequency shift to the square difference between the single-photon Rabi frequencies of the first and second lasers. In addition, the magnitude of the AC Stark frequency shift is positively correlated with the magnitude of the Rydberg resonance frequency of the atom, which can be expressed as:

[0073] δ AC1- δ AC =f1-f (3)

[0074] Represented by, where f is the atomic Rydberg resonance frequency when the output power of the target laser is the first laser power. And since the square of the single-photon Rabi frequency at the atom is positively correlated with the laser intensity at the atom, and the laser intensity is positively correlated with the laser power, the square of the single-photon Rabi frequency at the atom can be set to be positively correlated with the laser power. Therefore, different Rydberg resonance frequencies can be obtained by adjusting the laser power of the target laser. Combined with formula (1), formula (2) can be transformed into:

[0075]

[0076] Formula (3) can be transformed into:

[0077] δ AC1 -δ AC =AK(P1-P)=f1-f (5)

[0078] Where P1 is the second laser output power that is not equal to the first laser power, and f1 is the atomic Rydberg resonance frequency corresponding to the second laser power. Through formula (5), we can get:

[0079]

[0080] The proportionality coefficient between the laser power and the square of the first single-photon Rabi frequency can be determined based on any two groups of laser power and atomic Rydberg resonance frequency.

[0081] By using the AC Stark frequency shift as an intermediate quantity and combining the proportional coefficient between the laser power of the target laser and the square of the first single-photon Rabi frequency, the first positive correlation expression between the laser power of the target laser and the Rydberg resonance frequency of the atom captured by the first optical tweezers can be determined. This facilitates the direct determination of the above-mentioned proportional coefficient through the slope of the fitting straight line, and the first single-photon Rabi frequency of the atom captured by the first optical tweezers can be directly obtained based on the proportional coefficient. This can simplify the calculation process, improve the efficiency of obtaining the first single-photon Rabi frequency of the atom and the objective accuracy of the data, and thus improve the practicality and convenience of the laser positioning method.

[0082] According to some embodiments, obtaining the proportionality coefficient of the laser power of the target laser and the square of the first single-photon Rabi frequency includes:

[0083] obtaining a third positive correlation between the laser power of the target laser and the laser intensity at the atom captured by the first optical tweezers;

[0084] Obtaining a fourth positive correlation between the laser intensity and the square of the first single-photon Rabi frequency;

[0085] The proportional coefficient is determined based on the third positive correlation and the fourth positive correlation.

[0086] Since the target laser's power is positively correlated with the laser intensity at the atom, and the laser intensity is positively correlated with the square of the first single-photon Rabi frequency, it can be determined that the laser power and the square of the first single-photon Rabi frequency are positively correlated. Determining the proportionality coefficient based on this positive correlation can improve the objectivity of the proportionality coefficient, facilitate accurate acquisition of the first single-photon Rabi frequency, and thus improve the accuracy of the laser positioning method.

[0087] According to some embodiments, obtaining a second positive correlation between the AC Stark frequency shift and the Rydberg resonance frequency of the atom trapped by the first optical tweezers includes:

[0088] Determining a single-photon detuning coefficient of the atom trapped by the first optical tweezers based on a first laser frequency of the target laser and a second laser frequency of a reference laser, wherein the reference laser is a laser that is confocal with the target laser and has a constant laser power;

[0089] According to the single-photon detuning coefficient, a fifth positive correlation between the target laser, the AC Stark frequency shift, and the first single-photon Rabi frequency is determined.

[0090] It should be noted that the AC Stark frequency shift is inversely proportional to the single-photon detuning frequency of the atom. Therefore, through the first laser frequency of the target laser and the second laser frequency of the reference laser, equation (2) can be transformed into:

[0091]

[0092] The second positive correlation can be obtained by formula (2). Where Δ is the single-photon detuning frequency of the atom, and the single-photon detuning frequency Δ of the atom can be a set value. Substituting formula (7) into formula (5) yields:

[0093]

[0094] The above-mentioned proportionality coefficient K can be obtained by substituting the single-photon detuning frequency.

[0095] Since the AC Stark frequency shift is inversely proportional to the single-photon detuning frequency of the atom, the positive correlation between the AC Stark frequency shift caused by the target laser and the reference laser and the first single-photon Rabi frequency is determined through the single-photon detuning coefficient. The single-photon detuning frequency can be adjusted according to the laser wavelengths of the target laser and the reference laser, and the proportional coefficient can be calculated based on the single-photon detuning frequency. The first single-photon Rabi frequency can be solved based on the proportional coefficient and the first laser power of the target laser, thereby further improving the accuracy of the method for obtaining the first single-photon Rabi frequency. This can reduce the difficulty of laser positioning, improve the accuracy of laser positioning, and further improve the practicality of the laser positioning method.

[0096] According to some embodiments, obtaining the Rydberg resonance frequencies of at least two atoms trapped by the first optical tweezers based on at least two laser powers of the target laser includes:

[0097] When the laser power of the target laser remains unchanged, adjusting the excitation frequency of the target laser;

[0098] Obtaining a retention probability of the atoms captured by the first optical tweezers according to the excitation frequency;

[0099] The excitation frequency corresponding to the minimum retention probability is determined to be the first Rydberg resonance frequency mentioned above.

[0100] like Figure 4 As shown, Figure 4 Schematic diagram of the Rydberg absorption peak distribution of a laser positioning method based on optical tweezers provided in an embodiment of the present application. The horizontal axis of the image represents the excitation frequency of the target laser, the vertical axis represents the retention probability of the atom, and curves 1 to 4 respectively represent the Rydberg resonance frequency curves generated at the atom by a 780nm laser at different excitation powers.

[0101] When the probability of an atom's survival is minimized and its probability of loss is maximized, it can be assumed that the atom resonates with the Rydberg excitation light. The excitation frequency at this point can then be determined as the atom's Rydberg resonance frequency. This method reduces the difficulty of determining the Rydberg resonance frequency, improves the accuracy and objectivity of the data, and facilitates improved accuracy in fitting the proportional coefficient, thereby enhancing the accuracy and practicality of the laser positioning method.

[0102] According to some embodiments, before the step of acquiring the Rydberg resonance frequencies of at least two atoms trapped by the first optical tweezers according to the at least two laser powers of the target laser, the method further includes:

[0103] According to the geometric positional relationship among the first optical tweezers, the second optical tweezers, and the light spot of the target laser, the target laser is adjusted so that the light spot of the target laser uniformly covers the first optical tweezers and the second optical tweezers.

[0104] For example, the optical paths of the Rydberg excitation light and the target laser belonging to the first and second optical tweezers can be overlapped, so that the light spots of the first, second, and target lasers are geometrically aligned. Images of the light spots of the first, second, and target lasers can be captured using a CCD camera, and the incident optical path of the target laser can be adjusted based on the extent to which the light spot of the target laser covers the first and second optical tweezers in the image.

[0105] Before determining the relative position based on the single-photon Rabi frequency, adjusting the geometric overlap of the spot images of the first optical tweezers, the second optical tweezers and the target laser can reduce the initial difference between the first single-photon Rabi frequency and the second single-photon Rabi frequency, facilitate rapid determination of the relative position of the light spot, reduce the amount of calculation, and avoid the distance between the two optical tweezers exceeding the Rydberg radius, which affects the excitation effect of the atoms, thereby improving the practicality of the laser positioning method.

[0106] According to some embodiments, determining the relative position of the target laser spot relative to the first optical tweezers and the second optical tweezers based on the first single-photon Rabi frequency and the second single-photon Rabi frequency includes:

[0107] The offset of the spot center of the target laser relative to the geometric centers of the first optical tweezers and the second optical tweezers is determined according to the frequency difference between the first single-photon Rabi frequency and the second single-photon Rabi frequency.

[0108] For example, when the spot center of the target laser coincides with the geometric center of the first optical tweezers and the second optical tweezers and the first single-photon Rabi frequency is greater than the second single-photon Rabi frequency, it can be considered that the spot center of the target laser is offset toward the first optical tweezers relative to the above-mentioned geometric center.

[0109] like Figure 5-1 As shown, Figure 5-1 A schematic diagram of a laser positioning method based on optical tweezers provided in an embodiment of the present application, in which the spot center of the target laser is different from the equilibrium position of the two optical tweezers. The intersection of the two dotted lines in the figure is the spot center of the target laser. At this time, the spot center is offset to the right and downward relative to the geometric center.

[0110] By determining the offset of the spot center of the target laser through the above method, it is convenient to accurately locate the equilibrium position between the first optical tweezers and the second optical tweezers, and to facilitate the adjustment of the target laser.

[0111] According to some embodiments, the above-mentioned laser positioning method based on optical tweezers further includes:

[0112] When the frequency difference is greater than a preset difference, the target laser is adjusted so that the light spot of the target laser moves toward the direction of the optical tweezers with a smaller single-photon pulling ratio frequency.

[0113] For example, the preset difference may be 1% of the standard single-photon Rabi frequency. The moving distance of the target laser spot may be determined based on the quantitative relationship between the frequency difference and the preset difference, and the adjustment method of the target laser may be determined based on the moving distance of the spot.

[0114] like Figure 5-2 As shown, Figure 5-2 A schematic diagram of a laser positioning method based on optical tweezers provided in an embodiment of the present application, wherein the center of the target laser spot is the same as the equilibrium position of the two optical tweezers, and the target laser spot is adjusted according to the frequency difference so that the center of the target laser spot coincides with the equilibrium position, so that the positional relationship between the target laser spot and the first optical tweezers and the second optical tweezers is as follows: Figure 5-2 shown.

[0115] By adjusting the target laser through the above method, the atoms captured by the two optical tweezers can reach the Rydberg excited state at the same time, which can improve the excitation efficiency of the atoms and enhance the practicality of the laser positioning method.

[0116] like Figure 6 As shown, Figure 6 This is a schematic structural diagram of a dual-atom Rydberg excitation device provided in an embodiment of the present application. The lasers emitted by the first optical tweezers emitting unit 601 and the second optical tweezers emitting unit 602 are combined by a beam combiner 603, so that the propagation directions of the lasers of the first and second optical tweezers coincide. The laser beams are incident on a filter 604, and after being transmitted through the filter 604, they are incident on a first strong focusing lens 605. The focused laser beams are transmitted to a vacuum chamber 606, capturing two atoms. The first target laser beam emitted by the first target laser emitting unit 607 is reflected by a first reflector 608 and output to the filter 604. The filter 604 causes the optical paths of the optical tweezers laser beam and the first target laser beam to coincide, achieving geometrical coincidence of the light spots of the first, second, and first target laser beams. A second target laser beam is emitted by the second target laser emitting unit 609 in the opposite direction of the first target laser beam. After being reflected by a second reflector 610, it is focused by a second strong focusing lens 611 and incident on the vacuum chamber 606, achieving Rydberg excitation of the atoms. Among them, the vacuum cavity 606 includes an anti-Helmholtz coil 6061 and an MOT cooling light emitting unit 6062. The atoms will be decelerated in the vacuum cavity 606 and gathered at the center of the magnetic field of the Helmholtz coil to form a low-temperature cold atomic cluster, which is convenient for optical tweezers to capture.

[0117] like Figure 7 As shown, an embodiment of the present application provides an electronic device 700, including a memory 710, a processor 720, and a computer program 711 stored in the memory 710 and executable on the processor 720. When the processor 720 executes the computer program 711, the following steps are implemented:

[0118] acquiring Rydberg resonance frequencies of at least two atoms trapped by the first optical tweezers according to at least two laser powers of the target laser;

[0119] determining a first single-photon Rabi frequency of the atom trapped by the first optical tweezers and a first laser power corresponding to the first single-photon Rabi frequency based on the at least two laser powers and the at least two Rydberg resonance frequencies;

[0120] When the target laser is at the first laser power, obtaining a second single-photon Rabi frequency of the atom trapped by the second optical tweezers;

[0121] The relative position of the target laser spot relative to the first optical tweezers and the second optical tweezers is determined according to the first single-photon Rabi frequency and the second single-photon Rabi frequency.

[0122] In the specific implementation process, when the processor 720 executes the computer program 711, it can achieve Figure 1 Any implementation manner in the corresponding embodiments.

[0123] Since the electronic device introduced in this embodiment is a device used to implement a device in the embodiment of the present application, based on the method introduced in the embodiment of the present application, technical personnel in this field can understand the specific implementation of the electronic device of this embodiment and its various variations. Therefore, how the electronic device implements the method in the embodiment of the present application is not introduced in detail here. As long as the equipment used by technical personnel in this field to implement the method in the embodiment of the present application falls within the scope of protection to be protected by this application.

[0124] Those skilled in the art will appreciate that the embodiments of the present application can be provided as methods, systems, or computer program products. Therefore, the present application can adopt the form of a complete hardware embodiment, a complete software embodiment, or an embodiment in combination with software and hardware. Moreover, the present application can adopt the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to magnetic disk storage, CD-ROM, optical storage, etc.) that contain computer-usable program code.

[0125] The present application is described with reference to the flowcharts and / or block diagrams of the methods, devices (systems), and computer program products according to the embodiments of the present application. It should be understood that each process and / or box in the flowchart and / or block diagram, as well as the combination of the processes and / or boxes in the flowchart and / or block diagram, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, an embedded computer, or other programmable data processing device to produce a machine, so that the instructions executed by the processor of the computer or other programmable data processing device generate instructions for implementing the processes in the flowchart and / or block diagram. Figure 1 a process or multiple processes and / or boxes Figure 1 A device that provides the functions specified in a block or multiple blocks.

[0126] These computer program instructions may also be stored in a computer readable memory that can direct a computer or other programmable data processing device to work in a specific manner, so that the instructions stored in the computer readable memory produce an article of manufacture comprising an instruction device, which implements the process Figure 1 a process or multiple processes and / or boxes Figure 1 The function specified in one or more boxes.

[0127] These computer program instructions can also be loaded onto a computer or other programmable data processing device so that a series of operational steps are executed on the computer or other programmable device to produce a computer-implemented process, thereby providing the instructions executed on the computer or other programmable device for implementing the process. Figure 1 a process or multiple processes and / or boxes Figure 1 A step that specifies a function in one or more boxes.

[0128] The present application also provides a computer program product, which includes computer software instructions. When the computer software instructions are executed on a processing device, the processing device is caused to execute the following Figure 1 The process of the laser positioning method based on optical tweezers in the corresponding embodiment.

[0129] The above-mentioned computer program product includes one or more computer instructions. When the above-mentioned computer program instructions are loaded and executed on a computer, the above-mentioned process or function according to the embodiment of the present application is generated in whole or in part. The above-mentioned computer may be a general-purpose computer, a special-purpose computer, a computer network, or other programmable device. The above-mentioned 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 above-mentioned computer instructions may be transmitted from one website, computer, server or data center to another website, computer, server or data center via a wired (e.g., coaxial cable, optical fiber, digital subscriber line (DSL)) or wireless (e.g., infrared, wireless, microwave, etc.) method. The above-mentioned computer-readable storage medium may be any available medium that a computer can store or a data storage device such as a server or data center that includes one or more available media integrated therein. The above-mentioned available medium may be a magnetic medium (e.g., a floppy disk, a hard disk, a tape), an optical medium (e.g., a DVD), or a semiconductor medium (e.g., a solid-state drive (SSD)).

[0130] Those skilled in the art will clearly understand that, for the convenience and brevity of description, the specific working processes of the systems, devices and units described above can refer to the corresponding processes in the aforementioned method embodiments and will not be repeated here.

[0131] In the several embodiments provided in this application, it should be understood that the disclosed systems, devices and methods can be implemented in other ways. For example, the device embodiments described above are merely schematic. For example, the division of the above units is only a logical function division. In actual implementation, there may be other division methods, such as multiple units or components can be combined or integrated into another system, or some features can be ignored or not executed. Another point is that the mutual coupling or direct coupling or communication connection shown or discussed can be an indirect coupling or communication connection through some interfaces, devices or units, which can be electrical, mechanical or other forms.

[0132] The units described above as separate components may or may not be physically separate, and 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 these units may be selected according to actual needs to achieve the purpose of the solution of this embodiment.

[0133] In addition, the functional units in the various embodiments of the present application may be integrated into a single processing unit, or each unit may exist physically separately, or two or more units may be integrated into a single unit. The aforementioned integrated units may be implemented in the form of hardware or software functional units.

[0134] If the above-mentioned integrated unit is implemented in the form of 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 the present application, or the part that contributes to the prior art, or all or part of the technical solution can be embodied in the form of a software product, which is stored in a storage medium and includes several instructions for enabling a computer device (which can be a personal computer, server, or network device, etc.) to execute all or part of the steps of the above-mentioned methods in each embodiment of the present application. The aforementioned storage medium includes: various media that can store program codes, such as a USB flash drive, a mobile hard disk, a read-only memory (ROM), a random access memory (RAM), a magnetic disk or an optical disk.

[0135] In summary, the above embodiments are only used to illustrate the technical solutions of the present application, rather than to limit them. Although the present application has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present application.

Claims

1. A laser positioning method based on optical tweezers, characterized in that: include: acquiring Rydberg resonance frequencies of at least two atoms trapped by the first optical tweezers according to at least two laser powers of the target laser; determining a first single-photon Rabi frequency of the atom trapped by the first optical tweezers and a first laser power corresponding to the first single-photon Rabi frequency according to the at least two laser powers and the at least two Rydberg resonance frequencies; When the target laser is at the first laser power, obtaining a second single-photon Rabi frequency of the atom trapped by the second optical tweezers; The relative position of the target laser spot relative to the first optical tweezers and the second optical tweezers is determined according to the first single-photon Rabi frequency and the second single-photon Rabi frequency.

2. The laser positioning method based on optical tweezers according to claim 1, wherein The determining, based on the at least two laser powers and the at least two Rydberg resonance frequencies, a first single-photon Rabi frequency of the atom trapped by the first optical tweezers and a first laser power corresponding to the first single-photon Rabi frequency comprises: Obtaining a proportionality coefficient between the laser power of the target laser and the square of the first single-photon Rabi frequency; Determining a first positive correlation between the laser power of the target laser and the Rydberg resonance frequency of the atoms trapped by the first optical tweezers based on at least two of the laser powers and at least two of the Rydberg resonance frequencies; According to the proportionality coefficient, a first single-photon Rabi frequency of the atom captured by the first optical tweezers is determined when the target laser is at the first laser power.

3. The laser positioning method based on optical tweezers as claimed in claim 2, wherein: Determining a first positive correlation between the laser power of the target laser and the Rydberg resonance frequency of the atoms trapped by the first optical tweezers by using at least two laser powers and at least two Rydberg resonance frequencies includes: obtaining a second positive correlation between the AC Stark frequency shift and the Rydberg resonance frequency of the atom trapped by the first optical tweezers; A first positive correlation between the laser power of the target laser and the Rydberg resonance frequency of the atoms trapped by the first optical tweezers is determined according to the second positive correlation and the proportional coefficient.

4. The laser positioning method based on optical tweezers according to claim 3, wherein: The obtaining of a proportional coefficient between the laser power of the target laser and the square of the first single-photon Rabi frequency includes: acquiring a third positive correlation between the laser power of the target laser and the laser intensity at the atom captured by the first optical tweezers; acquiring a fourth positive correlation between the laser intensity and the square of the first single-photon Rabi frequency; The proportionality coefficient is determined based on the third positive correlation and the fourth positive correlation.

5. The laser positioning method based on optical tweezers according to claim 3, wherein: The step of obtaining a second positive correlation between the AC Stark frequency shift and the Rydberg resonance frequency of the atom captured by the first optical tweezers comprises: Determining a single-photon detuning coefficient of an atom trapped by the first optical tweezers based on a first laser frequency of the target laser and a second laser frequency of a reference laser, wherein the reference laser is a laser that is confocal with the target laser and has a constant laser power; A fifth positive correlation between the target laser, the AC Stark frequency shift, and the first single-photon Rabi frequency is determined according to the single-photon detuning coefficient.

6. The laser positioning method based on optical tweezers according to claim 1, wherein: The step of obtaining the Rydberg resonance frequencies of at least two atoms trapped by the first optical tweezers according to at least two laser powers of the target laser comprises: When the laser power of the target laser remains unchanged, adjusting the excitation frequency of the target laser; Obtaining, according to the excitation frequency, a retention probability of the atoms captured by the first optical tweezers; The excitation frequency corresponding to the minimum retention probability is determined to be the first Rydberg resonance frequency.

7. The laser positioning method based on optical tweezers according to claim 1, wherein: Before the step of acquiring the Rydberg resonance frequencies of at least two atoms trapped by the first optical tweezers according to the at least two laser powers of the target laser, the method further includes: According to the geometric positional relationship among the first optical tweezers, the second optical tweezers, and the light spot of the target laser, the target laser is adjusted so that the light spot of the target laser uniformly covers the first optical tweezers and the second optical tweezers.

8. The laser positioning method based on optical tweezers according to claim 7, wherein: The determining, according to the first single-photon Rabi frequency and the second single-photon Rabi frequency, a relative position of the target laser spot relative to the first optical tweezers and the second optical tweezers comprises: The offset of the spot center of the target laser relative to the geometric center of the first optical tweezers and the second optical tweezers is determined according to the frequency difference between the first single-photon Rabi frequency and the second single-photon Rabi frequency.

9. The laser positioning method based on optical tweezers according to claim 8, wherein: Also includes: When the frequency difference is greater than a preset difference, the target laser is adjusted so that the light spot of the target laser moves toward the direction of the optical tweezers with a smaller single-photon pulling ratio frequency.

10. An electronic device comprising a memory and a processor, characterized in that: The processor is configured to implement the steps of the laser frequency switching method according to any one of claims 1 to 9 when executing the computer program stored in the memory.

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