用于亚Hz量级线宽超稳激光频率噪声评估的高准确度低噪声频率电压转换器研制  

Development of a high-accuracy and low-noise frequency-voltage converter for sub-Hz linewidth ultra-stable laser frequency noise evaluation

作　　者：刘师彤 郭文阁[1,3] 闫露露 魏明明[1,3] 翟二江 张颜艳 高炜欣[1] 姜海峰[2,3] 张首刚[2,3] LIU Shi-tong;GUO Wen-ge;YAN Lu-lu;WEI Ming-ming;ZHAI Er-jiang;ZHANG Yanyan;GAO Wei-xin;JIANG Hai-feng;ZHANG Shou-gang(Xi′an Shiyou University,Xi′an 710065,China;National Time Service Center,Chinese Academy of Science,Xi′an 710600,China;Key Laboratory of Time and Frequency Primary Standards,National Time Service Center,Chinese Academy of Sciences,Xi′an 710600,China)

机构地区：[1]西安石油大学,西安710065 [2]中国科学院国家授时中心,西安710600 [3]中国科学院时间频率基准重点实验室,西安710600

出　　处：《光电子．激光》2021年第4期339-343,共5页Journal of Optoelectronics·Laser

基　　金：西安石油大学研究生创新与实践能力培养计划项目(YCS19213097);西安石油大学研究生联合培养基地建设项目(西石大研2017第43号)资助项目;中科院西部之光项目“超稳激光频率精密测量”(中科院人字(2018)6号文件);中科院国际人才计划杰出学者项目(中科院际字(2019)1号);“西部青年学者”项目“光生微波源关键技术研究”(XAB2019B19);中国科学院国家授时中心“青年创新人才”项目“应用于飞秒光梳的新型控制算法研究”(国授发字[2019]5号);国家自然科学基金(91536217,61825505)。

摘　　要：超稳激光的频率噪声是评估超稳激光性能的一个重要指标,一般均需要借助频率电压转换装置将频率噪声转换为电压噪声来测量。目前市场上现有的频压转换芯片适用于工业控制领域,不能满足评估超稳激光所需的低噪声、高输入频率以及大带宽的需求。本文基于锁相环技术设计了一种准确度高、附加噪声低的频率电压转换器,介绍了其工作原理,并对其转换系数、准确度和附加频率噪声进行了测试。实验数据显示,该频压转换器在24.85MHz~25.19MHz频率区间内实现了频率-电压的线性转换;具有较高的准确度,在100kHz测量范围内,频压转换误差小于0.5dB;附加频率噪声在1Hz频偏处的频率噪声小于-10dB Hz2/Hz,在2Hz~100kHz的测试带宽内,噪底均低于-20 dBHz2/Hz,满足测试线宽在亚Hz水平的超稳激光器频率噪声的要求。The frequency noise of an ultra-stable laser is an important indicator for evaluating the performance of an ultra-stable laser.Generally,it is necessary to use a frequency to voltage conversion device to convert the frequency noise into voltage noise for measurement.The current frequency to voltage conversion chips on the market are suitable for the industrial control field,and cannot meet the low noise,high input frequency,and large bandwidth requirements for evaluating ultra-stable lasers.This paper designs a frequency to voltage converter with high accuracy and low additional noise based on phase-locked loop technology,introduces its working principle,and tests its conversion coefficient,accuracy and additional frequency noise.Experimental data shows that the frequency to voltage converter achieves a frequency to voltage linear conversion in the frequency range of 24.85 MHz to 25.19 MHz,with high accuracy.In the 100 kHz measurement range,the frequency to voltage conversion error is less than 0.5 dB.The frequency noise at the frequency deviation of 1 Hz is less than-10 dB Hz2/Hz,and the noise floor is less than-20 dB Hz2/Hz in the range from 2 Hz to 100 kHz,which meets the requirements of ultra-stable laser frequency noise with a test linewidth of 1 Hz.

关 键 词：频压转换 超稳激光 频率噪声 频压转换线性度 FFT分析 

分 类 号：TN24[电子电信—物理电子学]