基于短光纤循环自外差法的激光线宽测量  

Laser Linewidth Measurement Based on Recirculating Self-Heterodyne Method with Short Fiber

作　　者：高静[1,2] 焦东东 刘杰[1] 邓雪[1] 臧琦[1,2] 张翔[1,2] 王丹 张晓斐 刘涛 Gao Jing;Jiao Dongdong;Liu Jie;Deng Xue;Zang Qi;Zhang Xiang;Wang Dan;Zhang Xiaofei;Liu Tao(Key Laboratory of Time and Frequency Standards,National Time Service Center,Chinese Academy of Sciences,Xi'an,Shaanxi 710600,China;University of Chinese Academy of Sciences,Beijing 100049,China)

机构地区：[1]中国科学院国家授时中心时间频率基准重点实验室,陕西西安710600 [2]中国科学院大学,北京100049

出　　处：《光学学报》2021年第7期81-86,共6页Acta Optica Sinica

基　　金：国家自然科学基金(91636101,91836301);国家自然科学基金青年科学基金(11803041);国家重点研发计划(2016YFF0200200)。

摘　　要：提出了一种基于短光纤循环延迟自外差技术测量亚千赫兹激光器线宽的方法。采用延迟长度仅为2 km的循环延迟自外差干涉仪,实现了一系列不同延迟时间拍频信号的同时测量。通过仿真拟合了多组高阶拍频信号的功率谱,获得激光器的平均线宽为944 Hz,该结果与传统拍频法测得的激光线宽基本一致。所提方法不仅可以避免单次测量误差,而且能有效减小1/f频率噪声引起的频谱加宽,可精密测量窄线宽激光器的线宽。A recirculating delayed self-heterodyne method with a short fiber is proposed for the precise measurement of sub-kHz laser linewidth.Using the recirculating delayed self-heterodyne interferometer with an only 2 km delayed fiber,a series of beat signals with different delay times are simultaneously measured.By simulating and fitting the power spectra of multiple high-order beat signals,the average linewidth of 944 Hz for a laser is obtained,which is basically in agreement with that obtained by the traditional beat frequency method.The proposed method can not only avoid a single measurement error,but also effectively reduce the frequency broadening induced by the 1/f frequency noise,therefore it can be used as an accurate detection tool for the linewidth measurement of a narrow linewidth laser.

关 键 词：测量 窄线宽激光器 线宽测量 循环延迟自外差法 短延迟光纤 拍频信号 

分 类 号：TN247[电子电信—物理电子学]