摘要
We propose a method to directly measure phase-related noise characteristics of single-frequency lasers in the 728–980 nm band based on a 120°phase difference interferometer.Differential phase information of the laser under test is demodulated via the interferometer.Other parameters related to the phase noise characteristics such as linewidth at different observation time, phase/frequency noise, power spectrum density of phase/frequency fluctuation, and Allan deviation are further obtained.Frequency noise as low as 1 Hz^2/Hz can be measured using our system.Then the phase-related noise characteristics of two commercial lasers frequently used in cold atomic clocks are studied systematically by the method.Furthermore, several influencing factors and their relative evolution laws are also revealed, such as the pump current and frequency-locking control parameters.This would help to optimize the laser performance, select laser sources, and evaluate the system performance for cold atomic physics applications.
We propose a method to directly measure phase-related noise characteristics of single-frequency lasers in the 728–980 nm band based on a 120°phase difference interferometer.Differential phase information of the laser under test is demodulated via the interferometer.Other parameters related to the phase noise characteristics such as linewidth at different observation time, phase/frequency noise, power spectrum density of phase/frequency fluctuation, and Allan deviation are further obtained.Frequency noise as low as 1 Hz^2/Hz can be measured using our system.Then the phase-related noise characteristics of two commercial lasers frequently used in cold atomic clocks are studied systematically by the method.Furthermore, several influencing factors and their relative evolution laws are also revealed, such as the pump current and frequency-locking control parameters.This would help to optimize the laser performance, select laser sources, and evaluate the system performance for cold atomic physics applications.
作者
Xi Zhang
Fei Yang
Zi-Tong Feng
Jie-Jun Zhao
Fang Wei
Hai-Wen Cai
Rong-Hui Qu
张茜;杨飞;冯子桐;赵洁珺;魏芳;蔡海文;瞿荣辉(Key Laboratory of Space Laser Communication and Detection Technology, Shanghai Institute of Optics and Fine Mechanics, Chinese Academy of Sciences, Shanghai 201800, China;Center of Materials Science and Optoelectronics Engineering, University of Chinese Academy of Sciences, Beijing 100049, China)
基金
Project supported by the National Natural Science Foundation of China(Grant Nos.61875214,61535014,and 61775225)
Scientific Innovation Fund of Chinese Academy of Sciences(Grant No.CXJJ-17S010)
