A method and apparatus for in-situ measurement of temperature in an atomic gas chamber

Abstract

This invention relates to the field of atomic magnetometer technology, specifically to a method and apparatus for in-situ measurement of atomic chamber temperature. In this invention, the atomic spin relaxation rate is obtained by measuring the linewidth of the resonance curve. The atomic spin exchange collision rate is obtained by fitting the atomic spin relaxation rate under different pump power densities, thereby acquiring the atomic chamber temperature and achieving accurate, in-situ measurement of the chamber's internal temperature. Compared to existing methods that use thermistors for contact temperature measurement of the chamber surface, this method requires no additional components. It utilizes atomic response signals to perform in-situ measurement of the temperature inside the atomic chamber, improving the accuracy of temperature measurement and providing necessary conditions for optimizing magnetometer system parameters.

Description

Technical Field

[0001] This invention relates to the field of atomic magnetometer technology, specifically to a method and apparatus for in-situ measurement of the temperature of an atomic gas chamber. Background Technology

[0002] Precision magnetic field measurement is of great significance for cutting-edge scientific research in life sciences, physics, and earth sciences, as well as for major national engineering projects. In recent years, with the development of quantum precision measurement technology, atomic magnetometers based on the interaction of magnetism, light, and atoms have become a research hotspot for high-sensitivity magnetic field measurement. The alkali metal atom gas cell is the sensitive core of the atomic magnetometer; the atomic number density inside is directly proportional to the magnetometer's signal strength. To improve the signal-to-noise ratio of magnetic field measurements, the atomic number density is typically increased by heating the atomic gas cell. To suppress fluctuations in the magnetometer's output signal caused by variations in atomic number density, closed-loop temperature control of the atomic gas cell is necessary. Accurate measurement of the gas cell temperature is a crucial prerequisite for achieving highly stable closed-loop control; therefore, conducting high-precision gas cell temperature measurement is of great importance.

[0003] Currently, the main method for measuring the temperature of a gas chamber is contact-based, which involves attaching a thermistor to the chamber handle or surface. However, due to the thickness of the glass chamber, this contact-based method cannot accurately measure the temperature inside the chamber. Therefore, there is an urgent need to propose an in-situ method for measuring the temperature of an atomic gas chamber to achieve accurate measurement of the internal temperature and create conditions for optimizing the system parameters. Summary of the Invention

[0004] In view of this, the present invention provides an in-situ method and apparatus for measuring the temperature of an atomic gas chamber, so as to solve the problem that the temperature measurement of the internal temperature of the atomic gas chamber in the prior art cannot be accurately measured.

[0005] In a first aspect, the present invention provides an in-situ method for measuring the temperature of an atomic gas cell. The method includes: irradiating atoms in a heated atomic gas cell with a pump laser and applying a magnetic field to the atomic gas cell to polarize the atoms and induce a resonance state; acquiring the resonance curve of the atoms and determining the transverse relaxation rate of the atomic spin based on the linewidth of the resonance curve; changing the pump laser power density to determine the transverse relaxation rate of the atomic spin corresponding to different pump laser power densities; fitting the transverse relaxation rate of the atomic spin under different pump laser power densities based on the relationship between the transverse relaxation rate of the atomic spin and the pump rate to obtain fitting parameters, wherein the fitting parameters include the atomic spin exchange collision rate; determining the atomic number density based on the atomic spin exchange collision rate; and determining the atomic gas cell temperature based on the atomic number density and the saturated vapor pressure formula.

[0006] In this invention, the atomic spin relaxation rate is obtained by measuring the linewidth of the resonance curve. The atomic spin exchange collision rate is then obtained by fitting the atomic spin relaxation rate under different pump power densities, thereby acquiring the atomic chamber temperature and achieving accurate, in-situ measurement of the chamber's internal temperature. Compared to existing methods that use thermistors for contact temperature measurement of the chamber surface, this method requires no additional components. It utilizes atomic response signals to perform in-situ measurement of the temperature inside the atomic chamber, improving the accuracy of temperature measurement and providing necessary conditions for optimizing the magnetometer system parameters.

[0007] In one optional embodiment, irradiating atoms in a heated atomic gas cell with a pump laser and applying a magnetic field to the atomic gas cell to polarize the atoms and induce a resonance state includes: irradiating atoms in a heated atomic gas cell with a pump laser to polarize the atoms; applying a longitudinal main magnetic field and a transverse radio frequency magnetic field to the atomic gas cell; scanning the frequency of the transverse radio frequency magnetic field to induce a resonance state; acquiring the resonance curve of the atom and determining the transverse spin relaxation rate of the atom based on the linewidth of the resonance curve, including: fitting the frequency change during the transverse radio frequency magnetic field scanning process and the output signal change of the atomic magnetometer to acquire the resonance curve of the atom; determining the linewidth of the resonance curve based on the fitting parameters; and determining the transverse spin relaxation rate of the atom based on the relationship between the linewidth of the resonance curve and the transverse spin relaxation rate of the atom.

[0008] In one optional implementation, the following formula is used to fit the frequency changes during the transverse radio frequency magnetic field scanning process and the changes in the output signal of the atomic magnetometer:

[0009]

[0010] In the formula, S represents the output signal of the atomic magnetometer, ω represents the frequency of the transverse radio frequency magnetic field, Γ represents the linewidth of the resonance curve, and A and ω0 are fitting parameters.

[0011] In this invention, by using this formula to fit the frequency changes and the output signal changes of the atomic magnetometer during the transverse radio frequency magnetic field scanning process, a data basis is provided for determining the linewidth of the resonance curve.

[0012] In one optional embodiment, irradiating atoms in a heated atomic gas cell with a pump laser and applying a magnetic field to the atomic gas cell to polarize the atoms and induce a resonance state includes: irradiating atoms in a heated atomic gas cell with a pump laser to polarize the atoms; applying a longitudinal main magnetic field to the atomic gas cell; modulating the parameters of the pump laser to induce a resonance state; acquiring the resonance curve of the atom and determining the transverse relaxation rate of the atomic spin based on the linewidth of the resonance curve, including: fitting the parameter changes during the pump laser parameter modulation process and the output signal changes of the atomic magnetometer to acquire the resonance curve of the atom; determining the linewidth of the resonance curve based on the fitting parameters; and determining the transverse relaxation rate of the atomic spin based on the relationship between the linewidth of the resonance curve and the transverse relaxation rate of the atomic spin.

[0013] In this invention, atoms can be brought into a resonant state by radio frequency magnetic field modulation or by optical modulation.

[0014] In one alternative implementation, the relationship between the pump rate and the transverse relaxation rate of atomic spins is expressed by the following formula:

[0015]

[0016] In the formula, R2 represents the transverse relaxation rate of atomic spin, R p R represents the pumping rate. se R represents the atomic spin-exchange collision rate. rel This represents the residual relaxation rate.

[0017] In this invention, based on the formula, it can be seen that by increasing the pump rate, the influence of the spin exchange rate can be suppressed, thereby narrowing the linewidth, thus providing a data basis for determining the atomic spin exchange collision rate.

[0018] In one alternative implementation, the amplitude of the applied transverse radio frequency magnetic field satisfies the following formula:

[0019]

[0020] In the formula, B1 represents the amplitude of the transverse radio frequency magnetic field, R1 and R2 are the longitudinal and transverse relaxation rates of the atom, respectively, and γ is the atomic gyromagnetic ratio.

[0021] In this invention, the influence of the radio frequency magnetic field on the linewidth is reduced by limiting the amplitude of the applied transverse radio frequency magnetic field.

[0022] In one alternative implementation, the temperature of the atomic gas chamber is controlled in a closed loop during the in-situ temperature measurement of the atomic gas chamber.

[0023] In this invention, the temperature of the atomic gas chamber is controlled in a closed loop, thereby enabling the gas chamber temperature to reach a stable state relatively quickly.

[0024] Secondly, the present invention provides an in-situ temperature measurement device for an atomic gas cell, the device comprising: a resonance control module, used to irradiate atoms in a heated atomic gas cell with a pump laser and apply a magnetic field to the atomic gas cell to polarize the atoms and induce a resonance state; a relaxation rate determination module, used to acquire the resonance curve of the atoms and determine the transverse relaxation rate of the atomic spin based on the linewidth of the resonance curve; a temperature determination module, used to change the pump laser power density and determine the transverse relaxation rate of the atomic spin corresponding to different pump laser power densities; based on the relationship between the transverse relaxation rate of the atomic spin and the pump rate, fitting the transverse relaxation rate of the atomic spin under different pump power densities to obtain fitting parameters, the fitting parameters including the atomic spin exchange collision rate; determining the atomic number density based on the atomic spin exchange collision rate; and determining the atomic gas cell temperature based on the atomic number density and the saturated vapor pressure formula. Attached Figure Description

[0025] To more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0026] Figure 1 This is a schematic flowchart of an in-situ temperature measurement method for an atomic gas chamber according to an embodiment of the present invention;

[0027] Figure 2 This is a structural block diagram of an in-situ temperature measurement device for an atomic gas chamber according to an embodiment of the present invention. Detailed Implementation

[0028] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0029] According to an embodiment of the present invention, an embodiment of an in-situ measurement method for atomic gas chamber temperature is provided. It should be noted that the steps shown in the flowchart in the accompanying drawings can be executed in a computer system such as a set of computer-executable instructions. Furthermore, although a logical order is shown in the flowchart, in some cases, the steps shown or described may be executed in a different order than that shown here.

[0030] This embodiment provides a method for in-situ measurement of atomic gas cell temperature. Figure 1 This is a flowchart of an in-situ temperature measurement method for an atomic gas chamber according to an embodiment of the present invention, such as... Figure 1 As shown, the process includes the following steps:

[0031] Step S101: The atoms in the heated atomic gas cell are irradiated with a pump laser, and a magnetic field is applied to the atomic gas cell to polarize the atoms and bring them into a resonance state.

[0032] Specifically, this in-situ temperature measurement method for atomic gas chambers involves measuring the temperature of the atomic gas chambers within an atomic magnetometer. Since the atomic magnetometer requires heating of the atomic gas chambers during operation, this embodiment primarily measures the temperature within the heated atomic gas chambers. Therefore, before measurement, a heat source for heating the atomic gas chambers can be activated. Common heat sources such as thermocouples, lasers, and infrared heaters can be used. Furthermore, a temperature control circuit and related algorithms can be employed to implement closed-loop temperature control of the atomic gas chambers before measurement, allowing the chamber temperature to reach a stable state quickly, facilitating temperature measurement. The temperature control circuit and algorithm can utilize a 555 timer circuit and a PID control algorithm, among others.

[0033] In this atomic magnetometer, the atoms in the atomic gas cell can be atoms with suitable energy level structures, such as alkali metal atoms like rubidium and cesium. During operation, a pump laser (e.g., circularly polarized light) irradiates the atomic gas cell, causing electrons in the atoms to transition from the ground state to an excited state. After spontaneous emission from the excited state, the electrons return to the secondary energy level, polarizing the atoms and generating spin polarization. Then, under the influence of an external magnetic field, the polarized atoms undergo Larmor precession, generating a precession frequency. Measuring this frequency determines the magnitude of the external magnetic field. To detect this precession, a linearly polarized probe beam perpendicular to the pump light is typically used. When the probe beam passes through the polarized atoms, its polarization plane deflects, with the deflection angle proportional to the projection of the atom's spin along the propagation direction. Therefore, by measuring the deflection angle, the Larmor precession frequency can be calculated, thus determining the magnitude of the external magnetic field and obtaining the output signal of the atomic magnetometer.

[0034] In this embodiment, when measuring temperature, it is necessary to bring the atoms in the atomic gas chamber into a resonant state. Specifically, this can be achieved by applying an external magnetic field to induce the atoms into a resonant state, or by modulating the pump parameters to induce the atoms into a resonant state.

[0035] In an optional implementation, step S101 includes:

[0036] Step a1 involves irradiating the atoms in the heated atomic gas chamber with a pump laser to polarize them. The method and function of irradiating the atoms with a pump laser are the same as those of the pump laser used when the atomic magnetometer is working, and will not be described again here.

[0037] Step a2 involves applying a longitudinal main magnetic field and a transverse radio frequency magnetic field to the atomic gas cell. Specifically, the longitudinal main magnetic field applied during temperature measurement is a constant magnetic field, oriented in the same direction as the propagation direction of the pump laser. This longitudinal main magnetic field functions similarly to the external magnetic field used by the atomic magnetometer, causing the atoms in the atomic gas cell to undergo Larmor precession. The applied transverse radio frequency magnetic field is used to enable the atoms to enter a resonant state; this transverse radio frequency magnetic field is an alternating magnetic field, oriented perpendicular to the longitudinal main magnetic field.

[0038] Step a3: Scan the frequency of the transverse radio frequency magnetic field to bring the atom into a resonant state; by scanning the frequency of the transverse radio frequency magnetic field, that is, gradually changing the frequency of the transverse radio frequency magnetic field, when the changed frequency matches the Larmor frequency of the atom, the spin of the atom will resonate.

[0039] In an optional implementation, step S101 includes:

[0040] Step b1 involves using a pump laser to irradiate the atoms in the heated atomic gas chamber, causing the atoms to polarize; please refer to step a1 above for details, which will not be repeated here.

[0041] Step b2: Apply a longitudinal main magnetic field to the atomic gas chamber; specifically, the applied longitudinal main magnetic field is the same as that applied in step a2, and will not be described again here.

[0042] Step b3 involves modulating the parameters of the pump laser to induce the atoms into a resonant state. Specifically, when using optical modulation to induce the atoms into a resonant state, the parameters of the pump laser can be modulated, such as the frequency, intensity, or phase, to induce the atoms into a resonant state.

[0043] Step S102: Obtain the resonance curve of the atom and determine the transverse relaxation rate of the atom's spin based on the linewidth of the resonance curve. Specifically, as described in step S101 above, the atom can be brought into a resonance state through magnetic field modulation or optical modulation. Therefore, the resonance curve during the process of the atom entering the resonance state can be determined by the changes in the modulation parameters and the output signal of the atomic magnetometer. The half-width at half-maximum (WHM) of the resonance curve is the linewidth of the resonance curve, and thus, the transverse relaxation rate of the atom's spin can be further determined using the linewidth of the resonance curve.

[0044] In an optional embodiment, when atoms are brought into a resonance state by magnetic field modulation, step S102 includes:

[0045] Step c1 involves fitting the frequency changes during the transverse radio frequency magnetic field scanning process with the changes in the output signal of the atomic magnetometer to obtain the resonance curve of the atom; specifically, when the pump laser polarizes the atom along the z-direction, a longitudinal main magnetic field B is applied along the z-direction. z Then the Larmor precession frequency of the atom along the z-direction is ω0 = γB z Where γ is the atomic gyromagnetic ratio. Additionally, the precession signal of atoms can be detected along the x-direction using a probe light to obtain the magnitude of the longitudinal main magnetic field, i.e., the output signal of the atomic magnetometer. When a radio frequency magnetic field 2B1cos(ωt) is applied along the y-direction, the atomic polarizability in the x-direction in the rotating coordinate system can be obtained using the rotating wave approximation method:

[0046]

[0047] Where R1 and R2 are the longitudinal and transverse relaxation rates of the atom, respectively, R p Let Γ be the pump rate, which is proportional to the pump optical power density, and Γ be the linewidth of the resonance curve. Furthermore, the output signal of the atomic magnetometer is proportional to the atomic polarizability in the x-direction. Therefore, based on the above equation, the frequency change during the transverse radio frequency magnetic field scanning process and the change in the output signal of the atomic magnetometer can be fitted to obtain the resonance curve. Linear least squares fitting can be used for fitting. The fitting result can be expressed by the following formula:

[0048]

[0049] In the formula, S represents the output signal of the atomic magnetometer, ω represents the frequency of the transverse radio frequency magnetic field, Γ represents the linewidth of the resonance curve, and A and ω0 are fitting parameters.

[0050] Step c2: Determine the linewidth of the resonance curve based on the fitting parameters; specifically, the corresponding linewidth Γ of the resonance curve can be obtained by calculating using the above formula.

[0051] Step c3: Determine the transverse relaxation rate of the atomic spin based on the relationship between the resonance curve linewidth and the transverse relaxation rate of the atomic spin. Specifically, the relationship between the resonance curve linewidth and the transverse relaxation rate of the atomic spin can be expressed as R² = 2πΓ. Therefore, after obtaining the resonance curve linewidth, substitute it into this relationship to obtain the transverse relaxation rate of the atomic spin.

[0052] Additionally, when applying a transverse radio frequency magnetic field, the amplitude B1 of the radio frequency magnetic field can be set to satisfy... This reduces the impact of radio frequency magnetic fields on linewidth.

[0053] In an optional embodiment, when atoms are brought into a resonant state by optical modulation, step S102 includes:

[0054] Step d1 involves fitting the parameter changes during the pump laser parameter modulation process and the output signal changes of the atomic magnetometer to obtain the resonance curve of the atom.

[0055] Step d2: Determine the linewidth of the resonance curve based on the fitting parameters.

[0056] Step d3: Determine the transverse relaxation rate of the atomic spin based on the relationship between the linewidth of the resonance curve and the transverse relaxation rate of the atomic spin.

[0057] Specifically, when optical modulation is used, the fitting formula corresponding to the radio frequency magnetic field mentioned above cannot be used. Therefore, it is necessary to refit the curve based on the changes in pump laser parameters such as laser frequency changes and the output signal of the atomic magnetometer during optical modulation. Then, the linewidth of the resonance curve is determined based on the fitting result. The method of determining the transverse relaxation rate of atomic spin based on the linewidth of the resonance curve is the same as the method in step c3 above, and will not be repeated here.

[0058] Step S103: Change the pump laser power density to determine the atomic spin transverse relaxation rate corresponding to different pump laser power densities. Specifically, when changing the pump laser power density, steps S101 and S102 can be performed at each pump laser power density to obtain the atomic spin transverse relaxation rate corresponding to each pump laser power density.

[0059] Step S104: Based on the relationship between the transverse relaxation rate of atomic spin and the pump rate, the transverse relaxation rate of atomic spin under different pump power densities is fitted to obtain fitting parameters, including the atomic spin exchange collision rate.

[0060] Specifically, there is a certain mapping relationship between pump laser power density and pump rate. Based on this mapping relationship and the atomic spin transverse relaxation rates corresponding to different pump laser power densities, the atomic spin transverse relaxation rates corresponding to different pump rates can be obtained. Specifically, the linear least squares fitting method can be used to fit the two, thereby obtaining the relationship between pump rate and atomic spin transverse relaxation rate, which is expressed by the following formula:

[0061]

[0062] In the formula, R2 represents the transverse relaxation rate of atomic spin, R p R represents the pumping rate. se R represents the atomic spin-exchange collision rate. rel This represents the residual relaxation rate. According to this formula, increasing the pump rate can suppress the influence of the spin exchange rate, thereby narrowing the linewidth; this is known as the optical narrowing effect.

[0063] Step S105: Determine the atomic number density based on the atomic spin exchange collision rate; specifically, the atomic spin exchange collision rate and the atomic number density have the following relationship:

[0064] R se =nνσ

[0065] In the formula, n is the atomic number density, and ν and σ are the relative thermal velocity and cross-sectional area of ​​alkali metal atoms.

[0066] Therefore, by using this relationship, after calculating the atomic spin-exchange collision rate, we can substitute it and the theoretical values ​​of ν and σ into this relationship to obtain the atomic number density.

[0067] Step S106: Determine the atomic chamber temperature based on the atomic number density and the saturated vapor pressure formula. Specifically, the saturated vapor pressure formula is expressed as follows:

[0068] n = (10 21.866+A-B / T ) / T

[0069] In the formula, T represents temperature, and A and B are alkali metal atomic density parameters. After calculating the atomic number density, the theoretical values ​​of A and B can be substituted to achieve in-situ measurement of the atomic gas chamber temperature.

[0070] The in-situ temperature measurement method for atomic gas chambers provided in this invention obtains the atomic spin relaxation rate by measuring the linewidth of the resonance curve, and then obtains the atomic spin exchange collision rate by fitting the atomic spin relaxation rate under different pump power densities, thereby acquiring the atomic gas chamber temperature and achieving accurate, in-situ measurement of the internal temperature of the gas chamber. Compared with existing methods that use thermistors for contact temperature measurement of the gas chamber surface, this method does not require additional devices, utilizes atomic response signals to perform in-situ temperature measurement of the atomic gas chamber, improves the accuracy of gas chamber temperature measurement, and provides necessary conditions for optimizing magnetometer system parameters.

[0071] As a specific application embodiment of the present invention, such as Figure 2 As shown, when a transverse radio frequency magnetic field is used to bring the atomic ensemble (a collection of a large number of atoms of the same type) in the atomic gas cell to a resonant state, the in-situ temperature measurement method of the atomic gas cell can be implemented according to the following procedure:

[0072] (1) Turn on the atomic gas chamber for heating, use pump laser to polarize the atoms along the longitudinal direction, apply longitudinal main magnetic field and transverse radio frequency magnetic field to make the atoms resonate.

[0073] (2) Scan the frequency of the radio frequency magnetic field to obtain the resonance curve of the atomic ensemble with respect to the longitudinal main magnetic field, and use the formula The test data are fitted, where A, ω0 and Γ are fitting parameters, Γ is the linewidth of the resonance curve, and the transverse relaxation rate of the atomic spin is R2 = 2πΓ.

[0074] (3) By varying the pump power density, repeat step (2) to perform resonance linewidth testing and obtain the curve of the change of atomic spin transverse relaxation rate with pump power.

[0075] (4) Based on the mapping relationship between pump power density and pump rate, calculate the pump rate under different pump power densities using the formula. (i.e., the narrowing effect of light pressure) is used to fit the transverse relaxation rate data of atomic spins under different pump rates, where R p R is the pumping rate. se and R rel These are the fitting parameters, Ri se =nνσ is the atomic spin-exchange collision rate, where n is the atomic number density, and ν and σ are the relative thermal velocity and cross-sectional area of ​​the alkali metal atoms. Based on the fitted R... se The atomic number density n can be calculated from the theoretical values ​​of ν and σ. Finally, the atomic number density value is substituted into the saturated vapor pressure formula n = (10 21.866+A-B / T The atomic chamber temperature T can be obtained by ) / T, thus enabling in-situ measurement of the atomic chamber temperature.

[0076] This embodiment also provides an in-situ temperature measurement device for an atomic gas chamber, which is used to implement the above embodiments and preferred embodiments; details already described will not be repeated. As used below, the term "module" can refer to a combination of software and / or hardware that performs a predetermined function. Although the device described in the following embodiments is preferably implemented in software, hardware implementation, or a combination of software and hardware, is also possible and contemplated.

[0077] This embodiment provides an in-situ temperature measurement device for an atomic gas chamber, such as... Figure 2 As shown, it includes:

[0078] The resonance control module 31 is used to irradiate the atoms in the heated atomic gas cell with a pump laser and apply a magnetic field to the atomic gas cell to polarize the atoms and bring them into a resonance state.

[0079] The relaxation rate determination module 32 is used to obtain the resonance curve of the atom and determine the transverse relaxation rate of the atom spin based on the linewidth of the resonance curve.

[0080] The temperature determination module 33 is used to change the pump laser power density and determine the atomic spin transverse relaxation rate corresponding to different pump laser power densities; based on the relationship between the atomic spin transverse relaxation rate and the pump rate, the atomic spin transverse relaxation rate under different pump power densities is fitted to obtain fitting parameters, the fitting parameters including the atomic spin exchange collision rate; the atomic number density is determined based on the atomic spin exchange collision rate; and the atomic cell temperature is determined based on the atomic number density and the saturated vapor pressure formula.

[0081] Further functional descriptions of the above modules and units are the same as those in the corresponding embodiments described above, and will not be repeated here.

[0082] Although embodiments of the invention have been described in conjunction with the accompanying drawings, those skilled in the art can make various modifications and variations without departing from the spirit and scope of the invention, and such modifications and variations all fall within the scope defined by the appended claims.

Claims

1. A method for in-situ measurement of the temperature of an atomic gas cell, characterized in that, The method comprises: Irradiating atoms in the atom cell in a heating state by using a pumping laser, and applying a magnetic field to the atom cell to polarize the atoms and make the atoms enter a resonance state; Obtaining a resonance curve of the atoms, and determining an atomic spin transverse relaxation rate based on a resonance curve line width; Changing a pumping laser power density to determine atomic spin transverse relaxation rates corresponding to different pumping laser power densities; Fitting the atomic spin transverse relaxation rates under different pumping light power densities based on a change relationship of the atomic spin transverse relaxation rate with respect to a pumping rate to obtain fitting parameters, wherein the fitting parameters comprise an atomic spin exchange collision rate; Determining an atomic number density based on the atomic spin exchange collision rate; Determining an atom cell temperature based on the atomic number density and a saturated vapor pressure formula; Irradiating atoms in the atom cell in a heating state by using a pumping laser, and applying a magnetic field to the atom cell to polarize the atoms and make the atoms enter a resonance state comprises: Irradiating atoms in the atom cell in a heating state by using a pumping laser to polarize the atoms; Applying a longitudinal main magnetic field and a transverse radio frequency magnetic field to the atom cell; Scanning a frequency of the transverse radio frequency magnetic field to make the atoms enter the resonance state; Obtaining a resonance curve of the atoms, and determining an atomic spin transverse relaxation rate based on a resonance curve line width comprises: Fitting a frequency change in the transverse radio frequency magnetic field scanning process and an output signal change of an atomic magnetometer to obtain the resonance curve of the atoms; Determining the resonance curve line width according to the fitting parameters; Determining the atomic spin transverse relaxation rate according to a relationship between the resonance curve line width and the atomic spin transverse relaxation rate.

2. The method of claim 1, wherein, The following formula is used to fit the frequency change in the transverse radio frequency magnetic field scanning process and the output signal change of the atomic magnetometer: where S represents the output signal of the atomic magnetometer, denotes the frequency of the transverse radio frequency magnetic field, denotes the resonance curve line width, and are fitting parameters.

3. The method of claim 1, wherein, Irradiating atoms in the atom cell in a heating state by using a pumping laser, and applying a magnetic field to the atom cell to polarize the atoms and make the atoms enter a resonance state comprises: Irradiating atoms in the atom cell in a heating state by using a pumping laser to polarize the atoms; Applying a longitudinal main magnetic field to the atom cell; Modulating parameters of the pumping laser to make the atoms enter the resonance state; Obtaining a resonance curve of the atoms, and determining an atomic spin transverse relaxation rate based on a resonance curve line width comprises: Fitting a parameter change in the pumping laser parameter modulation process and an output signal change of an atomic magnetometer to obtain the resonance curve of the atoms; Determining the resonance curve line width according to the fitting parameters; Determining the atomic spin transverse relaxation rate according to a relationship between the resonance curve line width and the atomic spin transverse relaxation rate.

4. The method of claim 1, wherein, The following formula is used to represent a relationship between a pumping rate and the atomic spin transverse relaxation rate: wherein denotes the atomic spin transverse relaxation rate, denotes the pumping rate, denotes the atomic spin exchange collision rate, denotes the residual relaxation rate.

5. The method of claim 1, wherein, An amplitude of the applied transverse radio frequency magnetic field satisfies the following formula: wherein B0represents the magnitude of the longitudinal static magnetic field, and T1and T2are the longitudinal and transverse relaxation rates of the atoms, respectively, γ is the gyromagnetic ratio of the atoms.

6. The method of claim 1, wherein, The temperature of the atom cell is closed-loop controlled during the atom cell temperature in-situ measurement process.

7. An in-situ apparatus for measuring the temperature of an atomic gas cell, characterized in that, The device comprises: A resonance control module configured to irradiate atoms in the atom cell in a heating state by using a pumping laser, and apply a magnetic field to the atom cell to polarize the atoms and make the atoms enter a resonance state; A relaxation rate determination module configured to obtain a resonance curve of the atoms, and determine an atomic spin transverse relaxation rate based on a resonance curve line width; The temperature determining module is configured to change the pumping laser power density, determine atomic spin transverse relaxation rates corresponding to different pumping laser power densities, fit the atomic spin transverse relaxation rates under different pumping light power densities based on a change relationship between the atomic spin transverse relaxation rate and the pumping rate, and obtain fitting parameters, wherein the fitting parameters include an atomic spin exchange collision rate; determine an atomic number density based on the atomic spin exchange collision rate; and determine an atomic cell temperature based on the atomic number density and a saturated vapor pressure formula. The method for determining the atomic cell temperature comprises the following steps: Irradiating atoms in the atomic cell in a heating state with a pumping laser, and applying a magnetic field to the atomic cell to polarize the atoms and make the atoms enter a resonance state, including: Irradiating atoms in the atomic cell in a heating state with a pumping laser to polarize the atoms; Applying a longitudinal main magnetic field and a transverse radio frequency magnetic field to the atomic cell; Scanning a frequency of the transverse radio frequency magnetic field to make the atoms enter a resonance state; Obtaining a resonance curve of the atoms, and determining an atomic spin transverse relaxation rate based on a line width of the resonance curve, including: Fitting a frequency change in the scanning of the transverse radio frequency magnetic field and an output signal change of the atomic magnetometer to obtain the resonance curve of the atoms; Determining the line width of the resonance curve according to the fitting parameters; Determining the atomic spin transverse relaxation rate according to a relationship between the line width of the resonance curve and the atomic spin transverse relaxation rate.

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