CN-120521535-B - Measurement method and device for detection tilt angle of single-component atomic shearing interferometer

CN120521535BCN 120521535 BCN120521535 BCN 120521535BCN-120521535-B

Abstract

The invention discloses a measuring method for detecting angles of a single-component atomic shearing interferometer, which is used for constructing an angle set of an angle oscillator, rotating a reflecting mirror between the moment that atoms are subjected to pi Raman laser and second pi/2 Raman laser, detecting shearing interference fringe images, traversing all angles in the angle set, and fitting and calculating an actual angle of a longitudinal direction of an imaging surface of a CCD camera relative to a Z-axis direction. The invention also discloses a measuring device for the detection tilt angle of the single-component atomic shearing interferometer. The invention can realize accurate measurement of the inclination angle of the detection system of the atomic shearing interferometer, thereby solving the problems of noise and system error caused by non-return of the inclination angle of the detection system of the atomic shearing interferometer and inhibiting the drift of differential measurement of the single-component atomic interferometer caused by inclination angle change.

Inventors

YAN SITONG
ZHOU LU
PANG YUXUAN
JIANG JUNJIE
HE CHUAN
ZHOU LIN
WANG JIN
ZHAN MINGSHENG

Assignees

中国科学院精密测量科学与技术创新研究院

Dates

Publication Date: 20260512
Application Date: 20250526

Claims (4)

1. A measuring method for the detection tilt angle of a single-component atomic shearing interferometer, utilizing a measuring device for the detection tilt angle of a single-component atomic shearing interferometer, the measuring device comprises a vacuum system (102), the vacuum system (102) comprises a cooling trapping region (1021), a detection region (1022) and an interference region (1023) which are arranged from bottom to top, the interference region (1023) is positioned in a magnetic shielding system (103), A single-component cold atomic group (101) is initially arranged in the cooling trapping area (1021), the single-component cold atomic group (101) is 87 Rb cold atomic group, Two pairs of mutually perpendicular horizontal cooling lasers (104) are incident into a cooling trapping area (1021), a detection system is arranged at the outer side of the detection area (1022), the detection system comprises a swinging angle device (110) and a CCD camera (109) arranged on the swinging angle device (110), the imaging surface of the CCD camera is perpendicular to the horizontal plane, a reflecting mirror (108) is arranged below the cooling trapping area, the reflecting mirror (108) is arranged on the deflection system (107), The longitudinal cooling laser A, the detection laser A, the first pi/2 Raman laser A, the pi Raman laser A and the second pi/2 Raman laser A are respectively vertically downwards and sequentially incident into an interference area (1023), a detection area (1022) and a cooling trapping area (1021) from the top of the interference area, The longitudinal cooling laser B, the detection laser B, the first pi/2 Raman laser B, the pi Raman laser B and the second pi/2 Raman laser B are reflected by the reflecting mirror and then sequentially enter the cooling trapping region (1021), the detection region (1022) and the interference region (1023); The CCD camera imaging plane is parallel to the Y 'axis of an imaging two-dimensional coordinate system in the transverse direction, the CCD camera imaging plane is parallel to the Z' axis of the imaging two-dimensional coordinate system in the longitudinal direction, the X axis and the Y axis of a three-dimensional coordinate system are positioned on the horizontal plane and are mutually perpendicular, the Z axis of the three-dimensional coordinate system is perpendicular to the horizontal plane, the horizontal rotation axis of the reflecting mirror (108) is parallel to the Y axis of the three-dimensional coordinate system, and the inclination angle of the swinging angle device (110) is adjusted so as to change the included angle of the longitudinal direction of the CCD camera imaging plane relative to the Z axis direction, and the measuring method is characterized by comprising the following steps: step 1, constructing an inclination angle set of an inclination angle device (110), selecting an inclination angle alpha from the inclination angle set, and realizing rotation of the selected inclination angle alpha on a CCD camera (109) through the inclination angle device (110); step 2, cooling and trapping the single-component cold atomic groups (101) in a cooling trapping area (1021) through a longitudinal cooling laser A, a longitudinal cooling laser B and two pairs of mutually perpendicular horizontal cooling lasers (104), and then throwing the single-component cold atomic groups into an interference area (1023) in a magnetic shielding system (103); Step 3, after a single-component cold atomic group (101) enters an interference area (1023) in a magnetic shielding system (103), mach-Zehnder atomic shearing interferometers are realized through first pi/2 Raman lasers, pi Raman lasers and second pi/2 Raman lasers, the first pi/2 Raman lasers comprise first pi/2 Raman lasers A and first pi/2 Raman lasers B, the pi Raman lasers comprise pi Raman lasers A and pi Raman lasers B, the second pi/2 Raman lasers comprise second pi/2 Raman lasers A and second pi/2 Raman lasers B, atoms are acted by the first pi/2 Raman lasers at the moment T 1 , atomic beam splitting is realized into two paths, after T time, the atoms are acted by the pi lasers at the moment T 2 , the inversion of the two paths of the atoms is realized, after T time, the atoms are further acted by the second pi/2 Raman lasers at the moment T 3 , the superposition of the two paths of the atoms is realized, and therefore, the atoms are realized, the rotation of the deflection system is realized under the action of a reflection mirror (108) between the pi Raman lasers and the second pi/2 Raman lasers ; Step 4, realizing free falling of the interfered single-component cold atomic groups (101) into a detection area (1022), applying detection laser resonating with the single-component cold atomic groups (101) to detect an atomic shearing interference fringe image, repeating the step 2 and the step 3 after the detection is finished, and re-detecting for a plurality of times to obtain a plurality of atomic shearing interference fringe images with an inclination angle alpha; step 5, calculating the phase difference of the atomic shearing interferometers at the upper energy level of the ground state and the energy level of the atomic shearing interference fringe image at the inclination angle alpha, and averaging the phase differences of all the atomic shearing interferometers to form the average phase difference of the atomic shearing interferometers at the upper energy level of the inclination angle alpha-and the energy level of the ground state , Rotating the swinging angle device (110) to the next measurement inclination angle alpha, returning to the step 2 until all inclination angles in the inclination angle set are traversed, and performing the step 6; Step 6, average phase difference of all groups of inclination angle alpha-atomic shearing interferometers with energy level on ground state and energy level on ground state Obtaining a first fitting straight line by linear fitting, and drawing The straight line is represented, and a first fitting straight line obtained by fitting and the first fitting straight line are obtained And the inclination angle alpha 0 corresponding to the abscissa of the intersection point is the actual included angle of the longitudinal direction of the CCD camera imaging surface relative to the Z-axis direction when the inclination angle of the swinging angle device (110) is set to be 0.
2. The method for measuring the detection tilt angle of a single component atomic shear interferometer of claim 1, wherein the tilt angles in the set of tilt angles are equi-differentially distributed centered on 0.
3. The method for measuring the detection tilt angle of a single component atomic shear interferometer of claim 1, wherein in step 4, the detection of the atomic shear fringe image comprises the step of applying a pump back laser before applying the detection laser.
4. The measurement method for the detection tilt angle of the single-component atomic shear interferometer according to claim 2, wherein the phase difference of the atomic shear interferometry of the energy level in the ground state and the energy level in the ground state of the individual atomic shear fringe image is obtained based on the steps of: The method comprises the steps of selecting an energy level interference fringe on a ground state and an energy level interference fringe under a ground state in the same atomic shearing interference fringe image, performing high sthene sinusoidal fitting on the two groups of interference fringes respectively, extracting phase information of the energy level interference fringe on the ground state and the energy level interference fringe under the ground state, calculating the difference of the phase information of the energy level interference fringe on the ground state and the energy level interference fringe under the ground state as an atomic shearing interferometer phase difference of the atomic shearing interference fringe image, and calculating the atomic shearing interferometer phase difference of each atomic shearing interference fringe image.

Description

Measurement method and device for detection tilt angle of single-component atomic shearing interferometer Technical Field The invention belongs to the field of precision measurement physics. In particular to a measuring method for the detection tilt angle of a single-component atomic shearing interferometer and also relates to a measuring device for the detection tilt angle of the single-component atomic shearing interferometer. Background In recent years, the development of laser-controlled atomic techniques has greatly driven the application of atomic interferometers in the fields of basic physical research and inertial physical quantity measurement. Atomic interferometry has become one of the most mature and widely used tools, particularly in terms of gravimetric measurement. Since the first measurement of gravitational acceleration using atomic interferometers in 1992, various related technologies have been vigorously developed, with shear phase shift reading methods being particularly prominent. A shearing phase shift reading method initiated by Sugarbaker et al (Phys. Rev. Lett.111,113002, 2013) remarkably reduces the influence of atomic number fluctuation and contrast variation on the phase by detecting spatial high-resolution interference fringes, and lays a technical foundation for real-time high-precision measurement. This technique then finds extended application in multiple dimensions, p.asenbaum et al (Phys. Rev. Lett.123,191101, 2020) applied to long baseline gravity-rotation synchronous measurements, d.yankelev et al (sci. Adv.6, eabd0650,2020) combined with moire effect extending the gravity dynamic range by three orders of magnitude, whereas g.w.hoth (appl. Phys. Lett.109,071113, 2016) and y.j.chen et al (Phys. Rev. Appl.12,014019, 2019) developed rotation measurement and multiaxial gyroscope schemes, respectively. Compared with traditional interferometry, the atomic shearing interferometry technology can obtain complete phase and contrast information of an atomic interferometer through single measurement, and has obvious advantages under the condition of long free evolution time. When the evolution time is increased, noise accumulation can lead to sharp reduction of the signal-to-noise ratio and fringe contrast of the system, phase information is difficult to extract by the traditional method when the contrast is low, and the shearing interference can still be effectively measured. However, the atomic interferometer adopting the shearing phase reading technology has the interference fringe phase directly related to the spatial position, and the relative position or angle change can introduce noise and systematic errors. In the previous study, yan (Phys. Rev. A108,063313,2023) et al effectively suppressed noise and systematic errors due to relative position changes by a Raman laser wave vector positive and negative tilt angle alternating measurement method. Another important source of such errors is the tilt angle of the atomic shear interferometer detection system in the vertical direction (i.e. the longitudinal direction of the imaging plane of the CCD camera) with respect to the gravitational direction, hereinafter referred to as the detection system tilt angle. When the tilt angle of the detection system is not zero, a highly correlated phase shift is introduced, and changes in tilt angle and fluctuations in atomic position also result in changes in phase noise. Atomic interferometers generally require long-term measurements, and application-type atomic interferometers also need to operate in environments with large vibration noise and temperature fluctuations. Therefore, accurate measurement of the inclination angle of the detection system is an important guarantee for realizing high-precision measurement of the atomic shearing interferometer, and the application potential of the atomic shearing interferometer in researches such as gravity measurement, rotation measurement and equivalent principle inspection is improved. Disclosure of Invention The invention mainly aims at the problems in the prior art, and provides a measuring method for the detection tilt angle of the single-component atomic shearing interferometer and a measuring device for the detection tilt angle of the single-component atomic shearing interferometer, so that the effective measurement of the angle of the longitudinal direction of the imaging surface of the CCD camera relative to the gravity direction can be realized. The above object of the present invention is achieved by the following technical means: the measuring device for the detection tilt angle of the single-component atomic shearing interferometer comprises a vacuum system, wherein the vacuum system comprises a cooling trapping area, a detection area and an interference area which are arranged from bottom to top, A single-component cold atomic group is initially arranged in the cooling trapping area, the single-component cold atomic group is 87 Rb cold at