用于引力波探测的星间激光干涉测量模拟系统

Inter-satellite Laser Interferometry Simulation System for Gravitational Wave Detection

星间激光干涉仪具有比地面干涉仪更长的干涉臂(10^(6)km),能够探测更低频段0.1 mHz~1 Hz的引力波。星间激光干涉仪具有典型的应答式外差干涉仪结构,其本质是一个光学锁相环。在地面环境下搭建模拟的星间激光干涉仪,成功将从激光器的频率锁定到稳频的主激光器频率上。结果显示:锁相环的锁定时间超过2×10^(4)s,满足了低频信号的探测条件;在较短位移和较长位移的不同条件下,干涉仪无粗大误差。经过分析得出:温度、气压等环境扰动带来的噪声是制约干涉仪精度的关键因素。

The inter-satellite laser interferometers have a longer interference arm(10^(6) km) than the ground interferometer and can detect gravitational waves in lower frequency bands 0.1 mHz~1 Hz.The inter-satellite laser interferometer has a typical structure of a transponder-type heterodyne interferometer,and its essence is an optical phase-locked loop.The simulated inter-satellite laser interferometer is built on the ground,and the frequency of the slave laser is successfully locked to the frequency of the stabilized master laser.The results show that the locking time is more than 2×10^(4) s,which meets the detection requirement of low-frequency signals.The interferometer has no coarse errors under different conditions of shorter and longer displacements.The noise caused by environmental disturbances such as temperature and air pressure is the key factor that restricts the accuracy of the interferometer.