A double diffraction rotational measurement method and system based on degenerate states of atomic kinetic energy

Abstract

This application belongs to the field of cold atom interferometry precision measurement technology, specifically disclosing a dual-diffraction rotation measurement method and system based on atomic kinetic energy degenerate states. The method employs a first-order Raman transition to achieve bidirectional beam splitting and combining of atoms, and a non-resonant high-intensity second-order Raman transition to achieve momentum reflection of atoms. This ensures that atoms remain in the same internal state F=2 throughout the interference process, effectively avoiding external field influences. Simultaneously, the highly symmetrical dual-diffraction structure suppresses systematic errors independent of the Raman wave vector direction. Utilizing the coupling characteristics of the internal and momentum states, phase information is directly obtained through the normalized probability of the atomic internal states, eliminating the need to distinguish momentum states, simplifying the detection process, shortening time, and enabling device miniaturization. This application improves measurement robustness and sensitivity, has a compact structure, and is suitable for high-precision inertial measurement.

Description

Technical Field

[0001] This application belongs to the field of cold atom interferometry precision measurement technology, and more specifically, relates to a method and system for measuring dual diffraction rotation based on atomic kinetic energy degeneracy. Background Technology

[0002] Cold atom interferometry gyroscopes, with their extremely high theoretical sensitivity and excellent long-term stability, are widely recognized as the next-generation core sensor surpassing traditional optical gyroscopes. This technology utilizes the wave-particle duality of atoms, coherently manipulating atoms with laser pulses to form matter-wave interference paths. Among the many technical approaches, the four-pulse Raman sequence (…) Due to its unique advantages in suppressing linear acceleration coupling, expanding the interference area, and realizing continuous measurement, the ) architecture has become a research hotspot in the current international precision measurement field.

[0003] However, traditional four-pulse Raman interferometers face insurmountable technical challenges in practical applications. Because atoms in different internal states after beam splitting do not respond entirely to external disturbances, subtle changes in environmental parameters can couple into the interference phase through differential mode effects, thus affecting measurement accuracy.

[0004] To address the aforementioned problems, existing technical literature discloses a representative four-pulse Raman interferometer gyroscope from the Paris Observatory in France. This scheme involves fabricating atoms in a magnetically insensitive... To avoid the first-order Zeeman effect, a method using multiple high-permeability magnetic shielding layers and active bias magnetic field compensation was employed to suppress the phase drift caused by the second-order Zeeman shift. However, this approach has the following drawbacks: First, it is difficult to completely eliminate residual background magnetic field variations and magnetic field noise during atomic flight; second, the complex shielding structure significantly increases the payload volume and mass, hindering system miniaturization. Furthermore, this experiment utilizes k-reversal technology, subtracting the forward (+k) and reverse (-k) signals of successively measured wave vectors to cancel the interferometer's optical drift and deduct most of the magnetic field system errors that do not change with the wave vector direction during alternating measurements. However, this differential technique can only suppress slow drifts with frequencies lower than the wave vector switching frequency; it cannot effectively eliminate high-frequency vibrations or instantaneous magnetic field fluctuations within the switching period. Summary of the Invention

[0005] To address the shortcomings of existing technologies, the purpose of this application is to provide a dual-diffraction rotation measurement method and system based on atomic kinetic energy degeneracy. This aims to solve the problem that in traditional four-pulse Raman interferometers, the responses of atoms in different internal states after atomic beam splitting to external disturbances are not completely consistent, and changes in environmental parameters are coupled into the interference phase through differential mode effects, thus affecting the accuracy of rotation measurement.

[0006] The first aspect of this application relates to a double diffraction rotation measurement method based on atomic kinetic energy degeneracy, comprising the following steps: Step S1: At the initial moment, send... State atoms apply Pulsed Raman light, forming and Two momentum states are split into beams; Step S2: In At that moment, the first non-resonant application Pulsed Raman light causes the atoms in the first atomic path to change from Flip to The atoms in the second atomic path are... Flip to ; Step S3: In At that moment, apply a second time Pulsed Raman light causes the atoms in the first atomic path to change from Flip to The atoms in the second atomic path are... Flip to ;in, This refers to the Raman pulse interval time. Step S4: In At that moment, atoms in the first atomic path and the second atomic path passed through Pulsed Raman light achieves coherent beam combining, and the three final states formed after beam combining are as follows: , , ; in, Pulsed Raman light and The propagation direction of pulsed Raman light is perpendicular to the atomic trajectory. Frequency difference of pulsed Raman light and atoms The leap resonance; For time intervals; The intensity of the pulsed Raman light needs to reach the saturation intensity of the second-order transition; steps S1 to S4 are performed based on an atomic interferometer gyroscope; Step S5: Detect the position after beam combining The atomic ratio is used to inversely calculate the interference phase difference accumulated by atoms in the first and second atomic paths; Step S6: Determine the relationship between the interference phase difference caused by the rotation of the atomic interferometer gyroscope and the angular velocity, and then measure the double diffraction rotation.

[0007] In some implementations, the detected state The relationship between the atomic ratio and the interference phase difference is as follows: ; in, The atom in the first atomic path undergoes one forward beam split, two reflections, and one reverse beam recombination, and the atom jumps to... The total phase of the pulsed Raman light-atomic interaction corresponding to the state; The interference phase difference; For the detected state The atomic ratio.

[0008] In some implementations, the relationship between the interference phase difference caused by the rotation of the atomic interferometer gyroscope and the rotation rate is as follows:

[0009] in, The interference phase difference is the output of the atomic interferometer gyroscope; The effective wave vector of the Raman beam; It is the acceleration due to gravity; The rotational rate that is sensitive to by the atomic interferometer gyroscope.

[0010] The second aspect of this application relates to a dual-diffraction rotation measurement system based on atomic kinetic energy degeneracy, comprising: an atomic interferometer gyroscope and a data processing module; An atomic interferometer gyroscope is used to initially... State atoms apply Pulsed Raman light, forming and Two momentum states are split into beams; Atomic interferometer gyroscopes are used in At that moment, the first non-resonant application Pulsed Raman light causes the atoms in the first atomic path to change from Flip to The atoms in the second atomic path are... Flip to ; Atomic interferometer gyroscopes are used in At that moment, apply a second time Pulsed Raman light causes the atoms in the first atomic path to change from Flip to The atoms in the second atomic path are... Flip to ; Atomic interferometer gyroscopes are used in At that moment, atoms in the first atomic path and the second atomic path passed through Pulsed Raman light achieves coherent beam combining, and the three final states formed after beam combining are as follows: , , ; in, Pulsed Raman light and The propagation direction of pulsed Raman light is perpendicular to the atomic trajectory. Frequency difference of pulsed Raman light and atoms The leap resonance; This refers to the Raman pulse interval time. The intensity of the pulsed Raman light needs to reach the saturation intensity of the second-order transition; The data processing module is used to detect the position after beam combining. The atomic ratio is used to inversely deduce the interference phase difference accumulated by atoms in the first and second atomic paths; and this is used to determine the relationship between the interference phase difference caused by the rotation of the atomic interferometer gyroscope and the rotation rate, thereby measuring the double diffraction rotation.

[0011] In some implementations, the data processing module detects that the data is in a state of... The relationship between the atomic ratio and the interference phase difference is as follows: ; in, The atom in the first atomic path undergoes one forward beam split, two reflections, and one reverse beam recombination, and the atom jumps to... The total phase of the pulsed Raman light-atomic interaction corresponding to the state; The interference phase difference; For the detected state The atomic ratio.

[0012] In some implementations, the relationship between the interference phase difference caused by the rotation of the atomic interferometer gyroscope and the angular velocity in the data processing module is as follows:

[0013] in, The interference phase difference is the output of the atomic interferometer gyroscope; The effective wave vector of the Raman beam; It is the acceleration due to gravity; The rotational rate interferometer sensitive to atomic interferometer gyroscopes is only sensitive to rotations perpendicular to the axis of rotation. Angular velocity component in the direction, T This is the Raman pulse interval.

[0014] In some implementations, the atomic interferometer gyroscope includes a two-dimensional magneto-optical trap, a three-dimensional magneto-optical trap, a vacuum interferometer region, and a detector region; Two-dimensional magneto-optical traps are used to cool rubidium atoms, producing cold atom clusters; Three-dimensional magneto-optical traps are used to trap cold atom clusters. By using a moving cluster technology and an acousto-optic modulator, a controllable frequency difference is generated between the upward and downward propagating trapping light, thereby providing directional net radiation pressure to the cold atom clusters and achieving vertical upward throwing. The vacuum interference region is used to observe cold atomic clusters rising and falling under the influence of gravity, passing through it sequentially. Pulse action; The detector region is used to apply detector light to atoms after pulsed treatment, and the fluorescence spectrum is used to measure the fluorescence. state and The population of the state is used to obtain the state of the atom. The atomic ratio is used to inversely calculate the interference phase difference.

[0015] Overall, the technical solutions conceived in this application have the following beneficial effects compared with the prior art: This application achieves symmetrical momentum beam splitting during atomic interference by controlling a single dual-frequency horizontal Raman beam perpendicular to the trajectory of the upward-thrown atom. Compared to traditional four-pulse atomic gyroscopes, the interference area is doubled, improving the sensitivity of the atomic interferometer gyroscope. More specifically, compared to traditional four-pulse Raman atomic gyroscopes, this application can suppress internal state-related common-mode noise and wave vector direction-independent systematic errors, and the final state detection is more miniaturized.

[0016] Suppressing common-mode noise: Traditional Raman interferometers use conventional first-order Raman resonance (such as traditional Raman atomic interferometers), which requires precise matching of the laser frequency to the two-photon resonance. This alters the internal states of atoms, hindering differential common-mode suppression. This application addresses this by introducing a larger two-photon detuning, namely... The frequency difference of the pulsed Raman light is set to a non-resonant state, while... The intensity of the pulsed Raman light needs to reach the saturation intensity of the second-order transition. Under conditions of large detuning and high intensity, atoms will simultaneously absorb and emit photons through virtual energy levels, equivalent to two consecutive Raman transitions, ultimately achieving internal state recovery and momentum reversal. Since the atoms are in the same internal state during the interference process, external disturbances (such as magnetic field fluctuations and laser frequency jitter) have the same effect on the two paths. The phase expressions of the two paths are symmetrical and will automatically cancel each other out in the phase difference calculation, improving measurement stability.

[0017] Increased sensitivity: Compared to the output phase of a traditional Raman four-pulse interferometer The interferometric phase difference of this application is exactly twice that of the traditional scheme. Under the same detection noise level, the phase sensitivity is increased by 2 times, which means that the scaling factor of the gyroscope is doubled and the measurement resolution is significantly improved.

[0018] Simplified configuration of dual-diffraction lasers: Traditional dual-diffraction Raman interferometers often need to avoid Raman beams perpendicular to the atomic trajectory, using the Doppler effect to induce momentum transitions in a single direction. To achieve momentum transitions in two directions, three or more Raman beams of different frequencies are required to eliminate the influence of the Doppler effect in the wave vector direction. This application simplifies the configuration of dual-diffraction lasers by controlling the Raman beam to be perpendicular to the atomic flight trajectory, requiring only a single dual-frequency Raman beam to achieve symmetrical momentum beam splitting.

[0019] Systematic errors: The highly symmetrical dual diffraction paths implemented in this application can effectively cancel systematic errors that are independent of the direction of the effective wave vector of the Raman light, thereby improving the long-term stability and environmental adaptability of the interferometer.

[0020] The detection method is simple: this application directly measures... Phase information can be obtained from the internal state probability of the state, without the need for complex time-of-flight detection or momentum-state space separation, which simplifies the system structure and is conducive to miniaturization and integration.

[0021] Based on the above principles, the embodiments of this application can be applied in the following scenarios: High-precision rotation measurement: Utilizing the phase multiplication characteristic, the atomic gyroscope achieves high-sensitivity rotation sensing; Basic physics research: used for high-precision measurements of Earth's rotation; Inertial navigation system: Combining miniaturized cold atom technology to construct a next-generation quantum inertial navigation unit with high precision and high stability. Attached Figure Description

[0022] Figure 1 This is a schematic diagram of a dual-diffraction rotation measurement method based on atomic kinetic energy degeneracy provided in an embodiment of this application.

[0023] Figure 2 This is a spatial trajectory diagram of the interferometer provided in the embodiments of this application.

[0024] Figure 3 This is a diagram of the laser frequency and atomic energy level of the second-order Raman transition provided in an embodiment of this application.

[0025] Figure 4 This is the spatiotemporal structure of the interferometer provided in the embodiments of this application.

[0026] Figure 5 This is a vacuum schematic diagram of the atomic interferometer gyroscope provided in the embodiments of this application.

[0027] In all the accompanying drawings, the same reference numerals are used to denote the same elements or structures, wherein: 1 is a two-dimensional magneto-optical trap component; 2 is a three-dimensional magneto-optical trap component; 3 is a selected state detection component; 4 is... 5 is a pulse component; 6 is an interference component. Pulse component; 7 is the first optical component. Detailed Implementation

[0028] To make the objectives, technical solutions, and advantages of this application clearer, the following detailed description is provided in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the scope of this application.

[0029] In this application, the term "and / or" describes the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent three cases: A existing alone, A and B existing simultaneously, and B existing alone. In this application, the symbol " / " indicates that the related objects are in an "or" relationship, for example, A / B means A or B.

[0030] In this application, the terms “first” and “second” are used to distinguish different objects, rather than to describe a specific order of objects.

[0031] In the embodiments of this application, the terms "exemplary" or "for example" are used to indicate that something is an example, illustration, or description. Any embodiment or design that is described as "exemplary" or "for example" in the embodiments of this application should not be construed as being more preferred or advantageous than other embodiments or design. Specifically, the use of the terms "exemplary" or "for example" is intended to present the relevant concepts in a specific manner.

[0032] In the description of the embodiments in this application, unless otherwise stated, "multiple" means two or more.

[0033] The embodiments of this application are described below with reference to the accompanying drawings.

[0034] This application employs a fountain-type cold atom interference structure, with a spatial structure design as follows: Figure 1 As shown, in The atom, initially launched vertically upwards, passes sequentially through the first Raman interaction region at the bottom and the second Raman interaction region at the top during its upward and downward trajectory. The core of this structure lies in utilizing Raman dual diffraction technology. By aligning the Raman light propagation direction perpendicular to the atomic trajectory, a single dual-frequency Raman light field can simultaneously excite the atom to undergo momentum recoil transitions in two opposite directions. Specifically, the atom passes through the first beam at the bottom... When pulsed Raman light reaches the first Raman interaction region, ±k transitions can occur simultaneously, resulting in beam splitting (double diffraction) and forming... and Two momentum-split states; subsequently, during the upward and downward propulsion processes, the atoms undergo one... Pulsed Raman light exposure causes two transverse momentum reversals; residual momentum remains after the above process. The atoms in the state can be removed with a clearing beam; finally, the atoms fall back into the first Raman interaction region and the beams combine to interfere.

[0035] like Figure 1 As shown, this application provides a double diffraction rotation measurement method based on atomic kinetic energy degeneracy, including the following steps: Step S1: First beam splitting ( Pulsed Raman light): The spatiotemporal structure design of the interferometer, such as Figure 2 As shown, in At that moment, the first application was made. Pulsed Raman light, Simultaneous occurrence of state atoms Bidirectional first-order Raman transition, forming and Two momentum states are split into beams; among them, For the effective wave vector of the Ranman light, for the counter-propagating dual-frequency Raman light, ; It is an internal state of the atom; Let be the initial momentum of the atom, where the initial momentum in the horizontal direction is approximately 0; To reduce Planck's constant; Step S2: First reflection ( Pulsed Raman light): in At a certain moment, when a non-resonant high-intensity Raman light is applied, the atom undergoes a second-order Raman transition, such as... Figure 3 As shown. After the first... After pulsed Raman light, the first atomic path is: momentum state is The atoms flip into a momentum state. The atom; simultaneously, the second atomic path is: momentum state is The atoms flip into dynamics The atoms achieved momentum reversal without changing their internal state; Step S3: Second reflection ( Pulsed Raman light): in At that moment, apply a second time Pulsed Raman light, the first atomic path is: momentum state is The atoms flip into a momentum state. The first atom; similarly, the second atom's path is: momentum state is The atoms flip into a momentum state. The atoms, the direction of their momentum reverses again, causing the two paths to tend to coincide in space. Step S4: First Bundle Combination (First) Pulsed Raman light): in At that moment, the two paths of atoms overlapped in space and passed through the last beam. Pulsed Raman light achieves coherent beam combining, and the three final states formed after beam combining are as follows: , , The complete first and second atomic paths are as follows: Figure 3 As shown.

[0036] in, Frequency difference of pulsed Raman light and atoms The transition resonance; pulse width correspondence The pulse propagates in a direction approximately perpendicular to the atomic trajectory to induce bidirectional symmetrical beam splitting. The frequency difference of the pulsed Raman light needs to be set to a non-resonant state. If conventional first-order Raman resonance is used, i.e., the laser frequency is precisely matched to the two-photon resonance, the atomic internal state will change, which is not conducive to differential common-mode suppression. However, this application introduces a large two-photon detuning. Under the conditions of large detuning and high light intensity, the atom will simultaneously absorb and emit photons through the virtual energy level, which is equivalent to two consecutive Raman transitions, ultimately achieving internal state recovery and momentum reversal. Figure 4 As shown. The detuning amount needs to be precisely calculated based on the atomic momentum; the pulse width corresponds to... The pulse intensity must reach the saturation intensity of a second-order transition (similar to a second-order Bragg transition) to ensure efficient momentum reversal, and the propagation direction must be perpendicular to the atomic trajectory. The application of the four laser beams must be precisely synchronized with the atomic trajectory to ensure that the atoms are in the predetermined positions when the pulse is applied; typical timing parameters are: the first... Pulsed Raman light in Apply at any time, for the first time Pulsed Raman light in Apply at the moment, the second time Pulsed Raman light in Apply at the moment, the second time Pulsed Raman light in Apply at any time ( (the interval between adjacent pulses); Step S5: The output signal of the atomic interferometer gyroscope reflects the distribution of the final-state atoms, which is then detected by detecting the atoms in a specific energy level after beam combining (e.g., ...). The atomic ratio of atoms can be used to inversely deduce the phase difference accumulated by atoms in the two paths. ; More specifically, assuming the positive direction of the Raman beam is the same as the positive x-axis, the phase of the interaction between the pulsed Raman beam and the atom for each path is calculated according to the following phase calculation principle: an atom undergoes a single positive Raman transition and acquires one photon phase. Reverse transition loses one photon phase No transition occurs and the phase remains unchanged; Based on the above calculation principles, the atom in the first atomic path undergoes one forward beam split, two reflections, and one reverse beam recombination, allowing us to calculate the transition of that atom to... The total phase of the pulsed Raman light-atomic interaction corresponding to the state is: (1) Based on the above calculations, the atom in the second atomic path undergoes one reverse beam split, two reflections, and one forward beam recombination. Therefore, the transition of this atom to... The total phase of the pulsed Raman-atomic interaction corresponding to the state is: (2) (3) In practical applications, by obtaining atomic interference and then... The probability of the state, and by inverse calculation Specifically: Since the pulsed Raman transition probabilities experienced by the first and second atomic paths are exactly the same, the atoms will transition to the desired state after each path. The amplitudes corresponding to the states are equal, that is... Therefore, it can be obtained that after atomic interference, the state is... The amplitude of the state is: (4) in, The two paths are in phase components, based on the relationship between amplitude and probability. After atomic interference, the state can be obtained. The probability is: (5) If probability normalization is taken into account Formula (5) can be simplified to: (6) Step S6: The atomic interferometer gyroscope adopts a four-pulse double diffraction structure based on first-order and second-order Raman steps. The relationship between the interference phase difference caused by rotation and the angular velocity is as follows: (7) in, The interference phase difference is the output of the atomic interferometer gyroscope; For a reverse-propagating dual-frequency Raman beam, the effective wave vector is given. ; It is the acceleration due to gravity; The rotational rate interferometer sensitive to atomic interferometer gyroscopes is only sensitive to rotations perpendicular to the axis of rotation. Angular velocity component in the direction; T This is the Raman pulse interval.

[0037] Based on the dual-diffraction rotation measurement method of atomic kinetic energy degeneracy, this application provides a corresponding upward-thrown atomic interferometer gyroscope, such as... Figure 5 As shown, it includes: A two-dimensional magneto-optical trap, located on one side of the cavity, is used to cool rubidium atoms and generate a slow atomic beam; The three-dimensional magneto-optical trap, located at the bottom of the cavity, consists of three sets of opposing cooling lights and a pair of anti-Helmholtz coils. The trap cools and confines the atomic clusters at the bottom of the vacuum cavity. Then, by using a moving cluster technique and an acousto-optic modulator, a controllable frequency difference is generated between the upward and downward propagating confinement light, thereby giving the cold atoms a directional net radiation pressure and achieving vertical upward throwing. In the vacuum interference region, cold atoms are ejected vertically upwards into the interference region. Under the influence of gravity, the atoms first rise and then fall, passing through... Pulse action; Detection zone: After the atoms have been pulsed, a probe light is applied, and the population of the two states is measured by fluorescence spectrum to obtain the probability that the atom is in the ground state, thereby inferring the interference phase.

[0038] More specifically, atoms that have undergone laser pre-cooling in the two-dimensional magneto-optical trap component 1 are pushed into the three-dimensional magneto-optical trap component 2 for further three-dimensional cooling by a directed laser. After sufficient cooling, the atoms are thrown upwards into the state-selection detection component 3. During rotation measurement, the state-selection laser is incident horizontally from the side and interacts with the atoms to achieve state selection. After being thrown upwards and downwards, the selected atoms return to the state-selection detection component 3 for final state detection. During rotation measurement, the atoms, after state selection, undergo... Pulse component 4 and Pulse component 6, respectively with Pulsed Raman light and Pulsed Raman light interaction achieves beam splitting-reflection-reunification of atomic wave packets, completing... The four-pulse atomic interference process ultimately achieves horizontal angular velocity measurement by performing final state detection in the selected state detection component 3.

[0039] Compared to the output phase of a traditional Raman four-pulse interferometer The output phase of this application is exactly twice that of the conventional scheme, a conclusion with significant technical implications: Increased sensitivity: Under the same level of detection noise, the phase sensitivity is increased by 2 times, which means that the scaling factor of the gyroscope is doubled and the measurement resolution is significantly improved.

[0040] Suppressing common-mode noise: The phase expressions of the two paths are symmetrical, and non-resonant high-intensity light... The pulse setting ensures that the internal state does not change during atomic interference. When external disturbances (such as magnetic field fluctuations or laser frequency jitter) have the same effect on the two paths, they will automatically cancel each other out in the phase difference calculation, thus improving measurement stability.

[0041] The detection method is simple: this application directly measures... Phase information can be obtained from the internal state probability of the state, without the need for complex time-of-flight detection or momentum-state space separation, which simplifies the system structure and is conducive to miniaturization and integration.

[0042] Based on the above principles, the embodiments of this application can be applied in the following scenarios: High-precision rotation measurement: Utilizing the phase multiplication characteristic, the atomic gyroscope achieves high-sensitivity rotation sensing; Basic physics research: used for high-precision measurements of Earth's rotation; Inertial navigation system: Combining miniaturized cold atom technology to construct a next-generation quantum inertial navigation unit with high precision and high stability.

[0043] It should be understood that expressions such as “comprising” and “may include” used in this application indicate the existence of the disclosed functions, operations, or constituent elements, and do not limit one or more additional functions, operations, and constituent elements. In this application, terms such as “comprising” and / or “having” are to be interpreted as indicating a particular characteristic, number, operation, constituent element, component, or combination thereof, but not to exclude the existence or possibility of adding one or more other characteristics, numbers, operations, constituent elements, components, or combinations thereof.

[0044] Furthermore, in this application, the expression "and / or" includes any and all combinations of the associated listed words. For example, the expression "A and / or B" may include A, may include B, or may include both A and B.

[0045] In the description of the embodiments of this application, it should be noted that, unless otherwise explicitly specified and limited, the term "connection" should be interpreted broadly. For example, "connection" can be a detachable connection or a non-detachable connection; it can be a direct connection or an indirect connection through an intermediate medium.

[0046] Furthermore, the mathematical concepts mentioned in the embodiments of this application, such as symmetry, equality, parallelism, and perpendicularity, are all limitations relative to the current technological level, rather than absolute and strict mathematical definitions. Slight deviations are allowed, and approximations of symmetry, equality, parallelism, and perpendicularity are all acceptable.

[0047] The above description is merely a specific embodiment of this application, but the scope of protection of this application is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in this application should be included within the scope of protection of this application. Therefore, the scope of protection of this application should be determined by the scope of the claims.

Claims

1. A method for measuring the rotational diffraction of atoms based on atomic kinetic energy degeneracy, characterized in that, Includes the following steps: Step S1: At the initial moment, send... The state atom is subjected to the first Pulsed Raman light, forming and Two momentum states are split into beams; Step S2: In At that moment, apply non-resonant Pulsed Raman light induces a second-order Raman transition in atoms, causing atoms in the first atomic path to... Flip to The atoms in the second atomic path are... Flip to ; Step S3: In At that moment, apply a second time Pulsed Raman light causes the atoms in the first atomic path to change from Flip to The atoms in the second atomic path are... Flip to ;in, This is the Raman pulse interval time; Step S4: In At that moment, atoms in the first atomic path and the second atomic path passed through Pulsed Raman light achieves coherent beam combining, and the three final states formed after beam combining are as follows: , , ; in, Pulsed Raman light and The propagation direction of pulsed Raman light is perpendicular to the atomic trajectory. Frequency difference of pulsed Raman light and atoms The leap resonance; The intensity of the pulsed Raman light needs to reach the saturation intensity of the second-order transition; steps S1 to S4 are performed based on an atomic interferometer gyroscope; Step S5: Detect the position after beam combining The atomic ratio is used to inversely calculate the interference phase difference accumulated by atoms in the first and second atomic paths; Step S6: Determine the relationship between the interference phase difference caused by the rotation of the atomic interferometer gyroscope and the angular velocity, and then measure the double diffraction rotation.

2. The method for measuring dual diffraction rotation according to claim 1, characterized in that, Detected in The relationship between the atomic ratio and the interference phase difference is as follows: ; in, The atom in the first atomic path undergoes one forward beam split, two reflections, and one reverse beam recombination, and the atom jumps to... The total phase of the pulsed Raman light-atomic interaction corresponding to the state; The interference phase difference; For the detected state The atomic ratio.

3. The method for measuring dual diffraction rotation according to claim 2, characterized in that, The relationship between the interference phase difference caused by the rotation of the atomic interferometer gyroscope and the angular velocity is as follows: in, The interference phase difference is the output of the atomic interferometer gyroscope; The effective wave vector of the Raman beam; It is the acceleration due to gravity; The rotational rate interferometer sensitive to atomic interferometer gyroscopes is only sensitive to rotations perpendicular to the axis of rotation. The angular velocity component in the direction.

4. A dual-diffraction rotation measurement system based on atomic kinetic energy degenerate states, characterized in that, include: Atomic interferometer gyroscope and data processing module; An atomic interferometer gyroscope is used to initially... State atoms apply Pulsed Raman light, forming and Two momentum states are split into beams; Atomic interferometer gyroscopes are used in At that moment, the first non-resonant application Pulsed Raman light causes the atoms in the first atomic path to change from Flip to The atoms in the second atomic path are... Flip to ; Atomic interferometer gyroscopes are used in At that moment, apply a second time Pulsed Raman light causes the atoms in the first atomic path to change from Flip to The atoms in the second atomic path are... Flip to ; Atomic interferometer gyroscopes are used in At that moment, atoms in the first atomic path and the second atomic path passed through Pulsed Raman light achieves coherent beam combining, and the three final states formed after beam combining are as follows: , , ; in, Pulsed Raman light and The propagation direction of pulsed Raman light is perpendicular to the atomic trajectory. Frequency difference of pulsed Raman light and atoms The leap resonance; This is the Raman pulse interval time; The intensity of the pulsed Raman light needs to reach the saturation intensity of the second-order transition; The data processing module is used to detect the position after beam combining. The atomic ratio is used to inversely deduce the interference phase difference accumulated by atoms in the first and second atomic paths; and this is used to determine the relationship between the interference phase difference caused by the rotation of the atomic interferometer gyroscope and the rotation rate, thereby measuring the double diffraction rotation.

5. The dual-diffraction rotation measurement system according to claim 4, characterized in that, The data processing module detected that it was in The relationship between the atomic ratio and the interference phase difference is as follows: ; in, The atom in the first atomic path undergoes one forward beam split, two reflections, and one reverse beam recombination, and the atom jumps to... The total phase of the pulsed Raman light-atomic interaction corresponding to the state; The interference phase difference; For the detected state The atomic ratio.

6. The dual-diffraction rotation measurement system according to claim 5, characterized in that, The relationship between the interference phase difference caused by the rotation of the atomic interferometer gyroscope and the angular velocity in the data processing module is as follows: in, The interference phase difference is the output of the atomic interferometer gyroscope; The effective wave vector of the Raman beam; It is the acceleration due to gravity; The rotational rate interferometer sensitive to atomic interferometer gyroscopes is only sensitive to rotations perpendicular to the axis of rotation. The angular velocity component in the direction.

7. The dual-diffraction rotation measurement system according to claim 4, characterized in that, An atomic interferometer gyroscope includes: a two-dimensional magneto-optical trap, a three-dimensional magneto-optical trap, a vacuum interferometer region, and a detector region; Two-dimensional magneto-optical traps are used to cool rubidium atoms, producing cold atom clusters; Three-dimensional magneto-optical traps are used to trap cold atom clusters. By using a moving cluster technology and an acousto-optic modulator, a controllable frequency difference is generated between the upward and downward propagating trapping light, thereby providing directional net radiation pressure to the cold atom clusters and achieving vertical upward throwing. The vacuum interference region is used to observe cold atomic clusters rising and falling under the influence of gravity, passing through it sequentially. Pulse action; The detector region is used to apply detector light to atoms after pulsed treatment, and the fluorescence spectrum is used to measure the fluorescence. state and The population of the state is used to obtain the state of the atom. The atomic ratio is used to inversely calculate the interference phase difference.

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