用于原子干涉仪的光学锁相环系统  

An Optical Phase-lock Loop System for Atom Interferometers

作　　者：白金海 胡栋 贡昊 王宇[1] BAIJinhai;HU Dong;GONG Hao;WANG Yu(Changcheng Institute of Metrology&Measurement,Beijing 100095,China)

机构地区：[1]航空工业北京长城计量测试技术研究所,北京100095

出　　处：《计测技术》2020年第6期26-30,共5页Metrology & Measurement Technology

基　　金：国家自然科学基金项目(61727819);国家“十三五”技术基础科研项目(JSJL2019205C002);航空基金项目(201956044001)。

摘　　要：相干激光的性能对原子干涉仪的测量精度有着重要影响。本文介绍了一种制备相干激光的外差式光学锁相环系统,实现了两台外腔半导体激光器频率和相位的同步,锁相后的激光拍频线宽低于1 Hz,10 MHz积分带宽内的残余相位噪音为0.002 rad2,频偏1~100 kHz范围内的相位噪音达到-100 dBc/Hz。并研究了闭环相位噪音对原子干涉仪的影响,在自由演化时间为200 ms、拉曼π脉冲时间为30μs、单次循环时间为1 s条件下,锁相后相位噪音对重力测量灵敏度的贡献为10μGal/(Hz)^(1/2),完全满足高精度原子干涉仪的使用需求。The performance of coherent laser has an important influence on the measurement accuracy of atom interferometry.We present a heterodyne optical phase-lock loop system for generating coherent laser.The frequency and phase synchronization of two external cavity semiconductor lasers are realized.The laser beat signal linewidth is less than 1 Hz,the residual phase noise within 10 MHz integral bandwidth is 0.002 rad2,and the phase noise reaches a flat floor of-100 d Bc/Hz in the offset frequency range of 1 k Hz to 100 k Hz.We also researched the impact on the sensitivity of the atomic measurement.Using the 200 ms’interrogation time,the 30μs’πRaman pulse duration time and the 1 s’cycle time,we calculated that our system would allow us to reach a sensitivity to acceleration as low as 10μGal/(Hz)1/2,meet the needs of high precision atom interferometry completely.

关 键 词：光学锁相环 相位噪音 原子干涉仪 灵敏度 

分 类 号：TH744.3[机械工程—光学工程]