Method, device and system for commissioning an atomic gravimeter

Abstract

This invention discloses a debugging method and apparatus for an atomic gravimeter, and the atomic gravimeter itself, relating to the field of atomic gravimeter technology. This invention can control the Raman light source to change the frequency difference between two Raman beams, causing the two beams to interact with atomic groups in a vacuum chamber. A fluorescence collection device can detect the ground state energy level population of atoms in the vacuum chamber. The main unit can plot a Raman spectrum showing the probability of an atom being in the target ground state as a function of the frequency difference, based on the ground state energy level population. By determining whether the Raman spectrum meets the preset conditions corresponding to the target polarization state, the polarization state of the Raman light in the atomic gravimeter can be judged to be in the desired state.

Description

Technical Field

[0001] This invention relates to the field of atomic gravimeter technology, and in particular to the debugging method, apparatus and system of atomic gravimeter. Background Technology

[0002] An atomic gravimeter is a high-precision absolute gravimeter based on an atomic interferometer. In an atomic gravimeter, atomic clusters undergo beam splitting, reflection, and recombination, resulting in interference, through two-photon Raman transitions under the influence of laser pulses. These laser pulses are typically called Raman beams. According to the selection rules for transitions, Raman beams must not only satisfy the resonance condition for energy level transitions but also meet certain polarization conditions. Otherwise, the interaction mode and depth between the atomic clusters and the light will be affected, reducing the contrast of the interference fringes in the atomic gravimeter, and may even lead to a zero transition probability and the disappearance of the interference phenomenon. Therefore, whether the polarization state of the Raman beam meets the requirements is crucial for an atomic gravimeter.

[0003] In atomic gravimeters, polarization optical components such as waveplates are generally fastened by mechanical means. After long-term use, these polarization optical components may become loose, causing the polarization state of the Raman light to change and no longer meet the requirements. Therefore, it is necessary to adjust the polarization state of the Raman light. Figure 1 One method for adjusting the polarization state of Raman light in an atomic gravimeter is as follows: the mirror and quarter-wave plate in the atomic gravimeter are removed, and then a polarization analyzer is installed to adjust the polarization state of the Raman light entering the vacuum cavity. After adjustment, the polarization analyzer is removed and the mirror and quarter-wave plate are reinstalled. Figure 1 During the debugging of the scheme, the Raman light needs to be incident perpendicularly into the polarization analyzer. Since the polarization analyzer is separate from the vacuum cavity and the Raman light, alignment is difficult and errors are unavoidable. Therefore, the following method is used... Figure 1 The current approach cannot guarantee that the polarization state of the Raman light can be adjusted to the desired state, nor can it be determined whether the light receiving surface of the polarization analyzer is perpendicular to the incident Raman light. Furthermore, even after adjustment, it is impossible to know whether the polarization state of the Raman light is indeed in the desired state. Therefore, the industry needs to consider how to determine whether the polarization state of the Raman light from an atomic gravimeter is in the desired state. Summary of the Invention

[0004] This invention solves the technical problem of how to determine whether the polarization state of Raman light from an atomic gravimeter is in the desired state by providing a debugging method, apparatus, and system for an atomic gravimeter.

[0005] On the one hand, the present invention provides the following technical solution:

[0006] A method for debugging an atomic gravimeter, comprising:

[0007] Controlling the Raman light source to change the frequency difference between the two emitted Raman beams;

[0008] Raman spectra of the probability of an atom being in the target ground state as a function of the frequency difference are plotted based on the population of the ground state energy level detected by the fluorescence collection device.

[0009] Determine whether the Raman spectrum satisfies the preset conditions corresponding to the target polarization state;

[0010] Wherein, the Raman spectrum satisfying the preset condition indicates that the Raman light of the atomic gravimeter is in the target polarization state, and the Raman spectrum not satisfying the preset condition indicates that the Raman light of the atomic gravimeter is not in the target polarization state.

[0011] Preferably, the target polarization state includes linear polarization;

[0012] The preset conditions include: the amplitude of the co-directional resonance peak of the Raman spectrum is a first preset threshold or the amplitude ratio of the co-directional resonance peak to the through resonance peak of the Raman spectrum is a second preset threshold.

[0013] Preferably, the target polarization state includes circular polarization;

[0014] The preset conditions include: the amplitude of the through-beam resonance peak of the Raman spectrum is a third preset threshold or the amplitude ratio of the through-beam resonance peak to the in-phase resonance peak of the Raman spectrum is a fourth preset threshold.

[0015] Preferably, after determining whether the Raman spectrum satisfies the preset conditions corresponding to the target polarization state, the method further includes:

[0016] If the Raman spectrum does not meet the preset conditions, the preset control process is repeated until the Raman spectrum meets the preset conditions.

[0017] The preset control process includes: controlling the polarization device to change the polarization state of the two Raman beams; controlling the Raman light source to change the frequency difference between the two Raman beams; plotting the Raman spectrum based on the ground state energy level population; and determining whether the Raman spectrum satisfies the preset conditions.

[0018] Preferably, controlling the polarization device to change the polarization state of the two Raman beams includes:

[0019] Change the voltage of the polarization device.

[0020] On the other hand, the present invention also provides the following technical solution:

[0021] A calibration device for an atomic gravimeter, comprising:

[0022] The frequency difference control module is used to control the Raman light source to change the frequency difference between the two emitted Raman beams;

[0023] The Raman spectroscopy module is used to plot the Raman spectrum of the probability of an atom being in the target ground state as a function of the frequency difference, based on the population of the ground state energy level detected by the fluorescence collection device.

[0024] The Raman spectroscopy analysis module is used to determine whether the Raman spectrum meets the preset conditions corresponding to the target polarization state.

[0025] Wherein, the Raman spectrum satisfying the preset condition indicates that the Raman light of the atomic gravimeter is in the target polarization state, and the Raman spectrum not satisfying the preset condition indicates that the Raman light of the atomic gravimeter is not in the target polarization state.

[0026] Preferably, the calibration device for the atomic gravimeter also includes:

[0027] A loop control module is used to perform a preset control process repeatedly until the Raman spectrum meets the preset conditions if the Raman spectrum does not meet the preset conditions.

[0028] The preset control process includes: controlling the polarization device to change the polarization state of the two Raman beams; controlling the Raman light source to change the frequency difference between the two Raman beams; plotting the Raman spectrum based on the ground state energy level population; and determining whether the Raman spectrum satisfies the preset conditions.

[0029] On the other hand, the present invention also provides the following technical solution:

[0030] A calibration system for an atomic gravimeter includes a Raman light source, a vacuum chamber, a fluorescence collection device, a main unit, a first quarter-wave plate, and a first reflecting mirror;

[0031] The Raman light source is used to emit two Raman beams and change the frequency difference between the two Raman beams. The vacuum cavity, the first 1 / 4 wave plate, and the first reflector are arranged sequentially in the optical path of the two Raman beams. The two Raman beams are reflected back along the original path after reaching the first reflector.

[0032] The vacuum cavity contains atomic groups, and the fluorescence collection device is connected to the vacuum cavity. The fluorescence collection device is used to detect the ground state energy level population of the atoms in the vacuum cavity.

[0033] The host computer is connected to the Raman light source and the fluorescence collection device respectively. The host computer is used to control the Raman light source to change the frequency difference between the two Raman beams; to plot the Raman spectrum of the probability of an atom being in the target ground state as a function of the frequency difference based on the ground state energy level population; and to determine whether the Raman spectrum meets the preset conditions corresponding to the target polarization state. Wherein, if the Raman spectrum meets the preset conditions, it indicates that the Raman light of the atomic gravimeter is in the target polarization state, and if the Raman spectrum does not meet the preset conditions, it indicates that the Raman light of the atomic gravimeter is not in the target polarization state.

[0034] Preferably, the debugging system of the atomic gravimeter further includes a polarization device, which is disposed in the optical path between the Raman light source and the vacuum cavity, and is used to change the polarization state of the two Raman beams.

[0035] Preferably, the polarization device is a liquid crystal phase delay film, a grating, or a metasurface structure.

[0036] One or more technical solutions provided by this invention have at least the following technical effects or advantages:

[0037] This invention can change the frequency difference between two Raman beams by controlling the Raman light source, so that the two Raman beams interact with atomic groups in a vacuum cavity. The fluorescence collection device can detect the ground state energy level population of the atoms in the vacuum cavity. The host can plot the Raman spectrum of the probability of the atom being in the target ground state as a function of the frequency difference based on the ground state energy level population. By judging whether the Raman spectrum meets the preset conditions corresponding to the target polarization state, it can be determined whether the polarization state of the Raman light of the atomic gravimeter is in the desired state. Attached Figure Description

[0038] To more clearly illustrate the technical solutions in the embodiments of the present invention, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0039] Figure 1 This is a schematic diagram illustrating the principle of one debugging scheme for an atomic gravimeter.

[0040] Figure 2 This is a schematic diagram of the debugging system structure of the atomic gravimeter in an embodiment of the present invention;

[0041] Figure 3 This is a flowchart of the debugging method of the atomic gravimeter in an embodiment of the present invention;

[0042] Figure 4 This is a schematic diagram of co-directional Raman light and through-beam Raman light in an embodiment of the present invention;

[0043] Figure 5 This is a schematic diagram of the Raman spectrum in an embodiment of the present invention;

[0044] Figure 6 This is another schematic diagram of the debugging system of the atomic gravimeter in an embodiment of the present invention;

[0045] Figure 7 This is another flowchart of the debugging method of the atomic gravimeter in this embodiment of the invention;

[0046] Figure 8 This is a schematic diagram illustrating the relationship between the polarization extinction ratio and the voltage of the liquid crystal phase retardation film in an embodiment of the present invention;

[0047] Figure 9 This is a schematic diagram of the debugging device for the atomic gravimeter in an embodiment of the present invention. Detailed Implementation

[0048] The embodiments of the present invention provide a debugging method, apparatus and system for an atomic gravimeter, which solves the technical problem of how to determine whether the polarization state of the Raman light of an atomic gravimeter is in the desired state.

[0049] To better understand the technical solution of the present invention, the technical solution of the present invention will be described in detail below with reference to the accompanying drawings and specific embodiments.

[0050] like Figure 2 As shown, the debugging system of the atomic gravimeter in this embodiment includes a Raman light source, a vacuum chamber, a fluorescence collection device, a main unit, a first quarter-wave plate, and a first reflecting mirror. The Raman light source is used to emit two Raman beams and change the frequency difference between the two Raman beams. The vacuum chamber, the first quarter-wave plate, and the first reflecting mirror are sequentially arranged in the optical path of the two Raman beams. The two Raman beams are reflected back along their original path after reaching the first reflecting mirror. The vacuum chamber contains atomic clusters. The fluorescence collection device is connected to the vacuum chamber and is used to detect the ground state energy level population of the atoms in the vacuum chamber. The main unit is connected to the Raman light source and the fluorescence collection device respectively. The main unit is used to control the Raman light source to change the frequency difference between the two Raman beams. The Raman spectrum showing the probability of the atom being in the target ground state as a function of the frequency difference is plotted based on the ground state energy level population. It is determined whether the Raman spectrum meets the preset conditions corresponding to the target polarization state. The Raman spectrum meeting the preset conditions indicates that the Raman light of the atomic gravimeter is in the target polarization state, and the Raman spectrum not meeting the preset conditions indicates that the Raman light of the atomic gravimeter is not in the target polarization state.

[0051] The atomic gravimeter debugging method in this embodiment is applied to Figure 2 In the host, such as Figure 3 As shown, the debugging method for an atomic gravimeter includes:

[0052] Step S1: Control the Raman light source to change the frequency difference between the two emitted Raman beams;

[0053] Step S2: Based on the population of the ground state energy level detected by the fluorescence collection device, plot the Raman spectrum of the probability of the atom being in the target ground state as a function of the frequency difference.

[0054] Step S3: Determine whether the Raman spectrum satisfies the preset conditions corresponding to the target polarization state;

[0055] Among them, Raman spectra that meet the preset conditions indicate that the Raman light of the atomic gravimeter is in the target polarization state, while Raman spectra that do not meet the preset conditions indicate that the Raman light of the atomic gravimeter is not in the target polarization state.

[0056] When the polarization state of the Raman light emitted by the atomic gravimeter meets the requirements, the two Raman beams emitted by the Raman source should be in a linearly polarized or circularly polarized state. In this embodiment, the two Raman beams are combined and collimated by the same optical fiber and enter the vacuum cavity. The vacuum cavity contains atomic clusters that are cooled and trapped by a magneto-optical trap. Then, the two Raman beams are reflected back along their original path by the first reflecting mirror after passing through the first quarter-wave plate. In this way, two pairs of Raman beams propagating in opposite directions are formed in the vacuum cavity. Figure 4 The pairs k11, k22 and k21, k12 are shown. K21, k22 or k11, k12 are called co-directional Raman beams, while k11, k22 or k21, k12 are called counter-directional Raman beams. Due to the Doppler effect, atoms in a vacuum cavity can only absorb one pair of Raman beams (k21, k22 or k11, k12 or k11, k22 or k21, k12). The other pairs of Raman beams do not interact with the atomic clusters because they do not satisfy the resonance condition. By changing the frequency difference between two Raman beams, the resonant pair of Raman beams can be selected.

[0057] In this embodiment, the atoms in the atomic group can be rubidium-85 atoms, rubidium-87 atoms, etc. Taking rubidium-85 atoms as an example, the atoms initially start in the F=2 state. When the atoms interact with a pair of Raman beams, due to two-photon Raman transitions, some atoms will transition to the F=3 state, which is the target ground state. When the frequency difference between the two Raman beams is changed, such as from -6MHz to 6MHz, the Raman beams that resonate when the frequency difference is between -4.5MHz and -2.5MHz and between 2.5MHz and 4.5MHz are called through-beam Raman beams, while the Raman beams that resonate when the frequency difference is between -1MHz and 1MHz are called co-directional Raman beams. The resonance peak formed when through-beam Raman beams resonate is called the through-beam resonance peak, and the resonance peak formed when co-directional Raman beams resonate is called the co-directional resonance peak. If the two Raman beams are in the best linear polarization state, the Raman spectrum should be as follows: Figure 5As shown in the first Raman spectrum, the amplitudes of the two opposing resonance peaks are at their highest points, or the amplitude of the co-directional resonance peak is at its lowest point, or the amplitude ratio between the co-directional resonance peak and the opposing resonance peak is at its minimum; if the two Raman beams are in the best circular polarization state, the Raman spectrum should be as follows: Figure 5 As shown in the second Raman spectrum, the amplitude of the co-directional resonance peak is at its highest point, or the amplitudes of the two opposing resonance peaks are at their lowest point, or the amplitude ratio between the opposing resonance peak and the co-directional resonance peak is at its minimum. If the two Raman beams are neither in the best linear polarization state nor the best circular polarization state, the Raman spectrum will be in an intermediate state between the first and second Raman spectra, with the amplitudes of both the opposing and co-directional resonance peaks at moderate levels. Here, amplitude can be the highest value of the resonance peak or the integral of the resonance peak with respect to the frequency difference, and amplitude ratio can be the ratio of the highest values ​​of the resonance peaks or the ratio of the integrals of the resonance peaks with respect to the frequency difference. Therefore, if the target polarization state includes linear polarization, the preset conditions should include: the amplitude of the co-directional resonance peak in the Raman spectrum is at a first preset threshold or the amplitude ratio between the co-directional and opposing resonance peaks in the Raman spectrum is at a second preset threshold; if the target polarization state includes circular polarization, the preset conditions should include: the amplitude of the opposing resonance peak in the Raman spectrum is at a third preset threshold or the amplitude ratio between the opposing and co-directional resonance peaks in the Raman spectrum is at a fourth preset threshold. Among them, the target polarization state is the Raman light polarization state desired by the user; the amplitude of the same-direction resonance peak is the first preset threshold, representing that the amplitude of the same-direction resonance peak is at its lowest level; the amplitude ratio of the same-direction resonance peak to the through-beam resonance peak is the second preset threshold, representing that the amplitude ratio of the same-direction resonance peak to the through-beam resonance peak reaches its minimum; the amplitude of the through-beam resonance peak is the third preset threshold, representing that the amplitude of the through-beam resonance peak is at its lowest level; and the amplitude ratio of the through-beam resonance peak to the same-direction resonance peak is the fourth preset threshold, representing that the amplitude ratio of the through-beam resonance peak to the same-direction resonance peak reaches its minimum level.

[0058] Therefore, after the host computer generates the Raman spectrum, the host computer or technicians can determine whether the polarization state of the Raman light from the atomic gravimeter is in the desired state based on the Raman spectrum. For example, if the required polarization state of the Raman light from the atomic gravimeter is linear polarization, then the Raman spectrum should be... Figure 5 The first Raman spectrum in the image; if the polarization state of the Raman light from the atomic gravimeter is required to be circularly polarized, then the Raman spectrum should be... Figure 5 The second Raman spectrum in the text.

[0059] In this embodiment, if the Raman spectrum does not meet the preset conditions corresponding to the target polarization state, it means that the Raman light polarization state of the atomic gravimeter is not in the desired state. At this time, the Raman light polarization state should be adjusted to make the Raman light polarization state in the required state.

[0060] To ensure the Raman light polarization state of the atomic gravimeter is in the desired condition, such as... Figure 6As shown, the debugging system of the atomic gravimeter in this embodiment also includes a polarization device, a second quarter-wave plate, and a second reflecting mirror. The polarization device, the second quarter-wave plate, and the second reflecting mirror are sequentially arranged in the optical path between the Raman source and the vacuum cavity. The polarization device is used to change the polarization state of the two Raman beams, and the second reflecting mirror is used to reflect the two Raman beams into the vacuum cavity. Figure 7 As shown, after step S3, the debugging method of the atomic gravimeter also includes: step S4, if the Raman spectrum does not meet the preset conditions corresponding to the target polarization state, the preset control process is repeated until the Raman spectrum meets the preset conditions; the preset control process includes: controlling the polarization device to change the polarization state of the two Raman beams; controlling the Raman source to change the frequency difference between the two Raman beams; plotting the Raman spectrum according to the population of the ground state energy level; and determining whether the Raman spectrum meets the preset conditions.

[0061] The use of a second reflecting mirror can alter the optical path, thus facilitating the miniaturization of the atomic gravimeter. The polarization device can be a liquid crystal phase retardation film, a grating, or a metasurface structure. This embodiment uses a liquid crystal phase retardation film as the polarization device. Experiments in this embodiment have shown that changing the voltage of the liquid crystal phase retardation film can alter the polarization state of the two Raman beams, such as... Figure 8 As shown, the larger the polarization extinction ratio, the better the linear polarization; the smaller the polarization extinction ratio, the better the circular polarization. When the voltage of the liquid crystal phase retardation film is around -0.4V, the two Raman beams will be in the best circular polarization state; when the voltage of the liquid crystal phase retardation film is around -1.1V, the two Raman beams will be in the best linear polarization state. Thus, in step S4, controlling the polarization device to change the polarization state of the two Raman beams can include changing the voltage of the liquid crystal phase retardation film.

[0062] Therefore, in this embodiment, the voltage of the liquid crystal phase retardation film can be continuously changed. For example, the voltage of the liquid crystal phase retardation film can be gradually increased from -3V to 3V. After each change in the voltage of the liquid crystal phase retardation film, the frequency difference between the two Raman beams is varied from -6MHz to 6MHz, and a Raman spectrum is plotted. In this way, each liquid crystal phase retardation film voltage corresponds to one Raman spectrum. During the process of gradually increasing the voltage from -3V to 3V, the co-directional resonance peak and the opposite resonance peak will show a situation of waxing and waning. When the voltage of the liquid crystal phase retardation film is around -1.1V, the following can be obtained: Figure 5 The first Raman spectrum can be obtained when the voltage of the liquid crystal phase retardation plate is around -0.4V. Figure 5 The second Raman spectrum. If the Raman light polarization state of the atomic gravimeter is required to be linearly polarized, the voltage of the liquid crystal phase retardation film can be set to about -1.1V to achieve the goal; if the Raman light polarization state of the atomic gravimeter is required to be circularly polarized, the voltage of the liquid crystal phase retardation film can be set to about -0.4V to achieve the goal.

[0063] As described above, the debugging method and system of the atomic gravimeter in this embodiment can change the frequency difference between two Raman beams by controlling the Raman light source, so that the two Raman beams interact with the atomic groups in the vacuum cavity. The fluorescence collection device can detect the ground state energy level population of the atoms in the vacuum cavity. The host can plot the Raman spectrum of the probability of the atom being in the target ground state as a function of the frequency difference based on the ground state energy level population. By judging whether the Raman spectrum meets the preset conditions corresponding to the target polarization state, it can be determined whether the polarization state of the Raman light of the atomic gravimeter is in the desired state. When the Raman spectrum does not meet the preset conditions corresponding to the target polarization state, the polarization device can be controlled to change the polarization state of the two Raman beams. After each change in the polarization state of the two Raman beams, the frequency difference between the two Raman beams is controlled by the Raman light source until the Raman spectrum meets the preset conditions. This can make the polarization state of the Raman light of the atomic gravimeter in the desired state. In addition, the first 1 / 4 wave plate and the first reflector in this embodiment belong to the atomic gravimeter, compared to Figure 1 The debugging scheme eliminates the need to remove and install the first quarter-wave plate and the first reflecting mirror, and also eliminates the need to install a polarization analyzer, making debugging more convenient and reducing errors.

[0064] like Figure 9 As shown, this embodiment also provides a debugging device for an atomic gravimeter, including:

[0065] The frequency difference control module is used to control the Raman light source to change the frequency difference between the two emitted Raman beams;

[0066] The Raman spectroscopy module is used to plot the Raman spectrum of the probability of an atom being in the target ground state as a function of frequency difference, based on the population of the ground state energy level detected by the fluorescence collection device.

[0067] The Raman spectroscopy analysis module is used to determine whether the Raman spectrum meets the preset conditions corresponding to the target polarization state.

[0068] Among them, Raman spectra that meet the preset conditions indicate that the Raman light of the atomic gravimeter is in the target polarization state, while Raman spectra that do not meet the preset conditions indicate that the Raman light of the atomic gravimeter is not in the target polarization state.

[0069] Furthermore, the calibration apparatus for the atomic gravimeter also includes:

[0070] The loop control module is used to perform the preset control process repeatedly until the Raman spectrum meets the preset conditions if the Raman spectrum does not meet the preset conditions.

[0071] The preset control process includes: controlling the polarization device to change the polarization state of the two Raman beams; controlling the Raman source to change the frequency difference between the two Raman beams; plotting the Raman spectrum based on the ground state energy level population; and determining whether the Raman spectrum meets the preset conditions.

[0072] Although preferred embodiments of the invention have been described, those skilled in the art, upon learning the basic inventive concept, can make other changes and modifications to these embodiments. Therefore, the appended claims are intended to be interpreted as including both the preferred embodiments and all changes and modifications falling within the scope of the invention.

[0073] Obviously, those skilled in the art can make various modifications and variations to this invention without departing from its spirit and scope. Therefore, if these modifications and variations fall within the scope of the claims of this invention and their equivalents, this invention also intends to include these modifications and variations.

Claims

1. A method for debugging an atomic gravimeter, characterized in that, include: Controlling the Raman light source to change the frequency difference between the two emitted Raman beams; Raman spectra of the probability of an atom being in the target ground state as a function of the frequency difference are plotted based on the population of the ground state energy level detected by the fluorescence collection device. Determine whether the Raman spectrum satisfies the preset conditions corresponding to the target polarization state; Wherein, the Raman spectrum satisfying the preset condition indicates that the Raman light of the atomic gravimeter is in the target polarization state, and the Raman spectrum not satisfying the preset condition indicates that the Raman light of the atomic gravimeter is not in the target polarization state; The target polarization state includes linear polarization; the preset conditions include: the amplitude of the co-directional resonance peak of the Raman spectrum is a first preset threshold or the amplitude ratio of the co-directional resonance peak to the through resonance peak of the Raman spectrum is a second preset threshold. Alternatively, the target polarization state includes circular polarization; the preset conditions include: the amplitude of the through-beam resonance peak of the Raman spectrum is a third preset threshold or the amplitude ratio of the through-beam resonance peak to the in-phase resonance peak of the Raman spectrum is a fourth preset threshold.

2. The debugging method of the atomic gravimeter as described in claim 1, characterized in that, After determining whether the Raman spectrum satisfies the preset conditions corresponding to the target polarization state, the method further includes: If the Raman spectrum does not meet the preset conditions, the preset control process is repeated until the Raman spectrum meets the preset conditions. The preset control process includes: controlling the polarization device to change the polarization state of the two Raman beams; controlling the Raman light source to change the frequency difference between the two Raman beams; plotting the Raman spectrum based on the ground state energy level population; and determining whether the Raman spectrum satisfies the preset conditions.

3. The debugging method for the atomic gravimeter as described in claim 2, characterized in that, Controlling the polarization device to change the polarization state of the two Raman beams includes: Change the voltage of the polarization device.

4. A debugging device for an atomic gravimeter, characterized in that, include: The frequency difference control module is used to control the Raman light source to change the frequency difference between the two emitted Raman beams; The Raman spectroscopy module is used to plot the Raman spectrum of the probability of an atom being in the target ground state as a function of the frequency difference, based on the population of the ground state energy level detected by the fluorescence collection device. The Raman spectroscopy analysis module is used to determine whether the Raman spectrum meets the preset conditions corresponding to the target polarization state. Wherein, the Raman spectrum satisfying the preset condition indicates that the Raman light of the atomic gravimeter is in the target polarization state, and the Raman spectrum not satisfying the preset condition indicates that the Raman light of the atomic gravimeter is not in the target polarization state; The target polarization state includes linear polarization; the preset conditions include: the amplitude of the co-directional resonance peak of the Raman spectrum is a first preset threshold or the amplitude ratio of the co-directional resonance peak to the through resonance peak of the Raman spectrum is a second preset threshold. Alternatively, the target polarization state includes circular polarization; the preset conditions include: the amplitude of the through-beam resonance peak of the Raman spectrum is a third preset threshold or the amplitude ratio of the through-beam resonance peak to the in-phase resonance peak of the Raman spectrum is a fourth preset threshold.

5. The debugging device for the atomic gravimeter as described in claim 4, characterized in that, Also includes: A loop control module is used to perform a preset control process repeatedly until the Raman spectrum meets the preset conditions if the Raman spectrum does not meet the preset conditions. The preset control process includes: controlling the polarization device to change the polarization state of the two Raman beams; controlling the Raman light source to change the frequency difference between the two Raman beams; plotting the Raman spectrum based on the ground state energy level population; and determining whether the Raman spectrum satisfies the preset conditions.

6. A calibration system for an atomic gravimeter, characterized in that, Includes a Raman light source, a vacuum chamber, a fluorescence collection device, a main unit, a first quarter-wave plate, and a first reflecting mirror; The Raman light source is used to emit two Raman beams and change the frequency difference between the two Raman beams. The vacuum cavity, the first 1 / 4 wave plate, and the first reflector are arranged sequentially in the optical path of the two Raman beams. The two Raman beams are reflected back along the original path after reaching the first reflector. The vacuum cavity contains atomic groups, and the fluorescence collection device is connected to the vacuum cavity. The fluorescence collection device is used to detect the ground state energy level population of the atoms in the vacuum cavity. The host computer is connected to the Raman light source and the fluorescence collection device respectively. The host computer is used to control the Raman light source to change the frequency difference between the two Raman beams; to plot the Raman spectrum of the probability of an atom being in the target ground state as a function of the frequency difference based on the ground state energy level population; and to determine whether the Raman spectrum meets the preset conditions corresponding to the target polarization state. Wherein, if the Raman spectrum meets the preset conditions, it indicates that the Raman light of the atomic gravimeter is in the target polarization state, and if the Raman spectrum does not meet the preset conditions, it indicates that the Raman light of the atomic gravimeter is not in the target polarization state. The target polarization state includes linear polarization; the preset conditions include: the amplitude of the co-directional resonance peak of the Raman spectrum is a first preset threshold or the amplitude ratio of the co-directional resonance peak to the through resonance peak of the Raman spectrum is a second preset threshold. Alternatively, the target polarization state includes circular polarization; the preset conditions include: the amplitude of the through-beam resonance peak of the Raman spectrum is a third preset threshold or the amplitude ratio of the through-beam resonance peak to the in-phase resonance peak of the Raman spectrum is a fourth preset threshold.

7. The debugging system for the atomic gravimeter as described in claim 6, characterized in that, It also includes a polarization device, which is disposed in the optical path between the Raman light source and the vacuum cavity, and is used to change the polarization state of the two Raman beams.

8. The debugging system for the atomic gravimeter as described in claim 7, characterized in that, The polarization device is a liquid crystal phase delay film, a grating, or a metasurface structure.

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