Acceleration measurement method and device based on atomic interference in optical waveguide

Abstract

The invention discloses an acceleration measurement method based on atomic interference in an optical waveguide, which includes the following steps: S1, preparing a cold atomic group; S2, loading an optical waveguide: keeping the atomic group in a magnetic insensitive state, opening the optical waveguide, and putting the atomic group in the optical waveguide; S3, atomic interference: applying PI/2, PI and PI/2 light pulses to the atomic group through two beams of Raman light or Prague light to realize beam splitting and combining of the atomic group, and constructing an atom interferometer; and S4, imaging detection: after interference, letting the atomic group freely fall for a period of time, carrying out detection through CCD or PD, and calculating the axial acceleration of the optical waveguide according to the detection result. The method and the device have the advantages of simple principle, simple operation, high accuracy, and the like.

Description

technical field [0001] The invention mainly relates to the field of acceleration measurement equipment, in particular to an acceleration measurement method and device based on atomic interference in an optical waveguide. Background technique [0002] At present, most of the accelerometers on the market adopt traditional technology, and their main working principles include (1) vibrating wire type: a linear accelerometer supported by two identical string wires. String tension is greatly affected by material properties and temperature, so a precise temperature control device and string tension adjustment mechanism are required. (2) Pendulum integrating gyroscope: an instrument that uses a two-degree-of-freedom gyroscope with a certain pendulum on the rotation axis to measure acceleration. This kind of accelerometer relies on the gyro torque to balance the inertia moment. It can maintain high measurement accuracy in a large range, but the structure is complex, the volume is la...

AI Technical Summary

Problems solved by technology

This kind of accelerometer relies on the gyro torque to balance the inertia moment. It can maintain high measurement accuracy in a large range, but the structure is complex, the volume is large, and the price is relatively expensive.

At the same time, these accelerometers also have common shortcomings: 1. The long-term cumulative error is large; 2. The measurement sensitivity is far from the upper limit of quantum sensors.

The measurement accuracy of this type of scheme is mainly limited by the following two aspects: firstly, the potential well roughness of the magnetic field waveguide will cause decoherence and splitting of atomic groups in the condensed state; secondly, due to the large well depth of this type of magnetic trap, will cause a phase shift in atomic interactions

Adding current modulation in the kHz range to the trapped magnetic field current source can make the potential well smooth, but at the same time, it will introduce unnecessary heating effect to the atomic group, which will have a large negative impact, reduce the signal-to-noise ratio of interferometry, and thus affect the measurement sensitivity.

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