基于自参考源的高精度时间抖动测量  

Ultrahigh-precision measurement timing jitter based on self-reference source

作　　者：徐鹏[1,2] 刘元山 张建国 XU Peng;LIU Yuan-shan;ZHANG Jian-guo(State Key Laboratory of Transient Optics and Photonics, Xi′an Institute of Optics and Precision Mechanics, Chinese Academy of Sciences, Xi′an 710119, China;University of Chinese Academy of Sciences, Beijing 100049, China;Electronic Information School & Optical Image Analysis and Learning Center,Northwestern Polytechnical University, Xi′an 710072, China;Division of Electrical and Electronic Engineering, School of Engineering,London South Bank University, London SE1 0AA, UK)

机构地区：[1]中国科学院西安光学精密机械研究所瞬态光学与光子技术国家重点实验室,陕西西安710119 [2]中国科学院大学,北京100049 [3]西北工业大学电子信息学院&光学影像分析与学习中心,陕西西安710072 [4]伦敦南岸大学工程学院,英国伦敦SE10AA

出　　处：《光学精密工程》2020年第11期2429-2436,共8页Optics and Precision Engineering

基　　金：国家自然科学基金资助项目(No.61875226)。

摘　　要：时间抖动是衡量光频梳、低相噪激光器、微波光子雷达等低噪系统性能的核心参数,其精确测量已成为一项重要工作。传统的直接探测法受限于微波振荡器的本地噪声或光电探测器的噪声,测量精度较低,在实际应用中无法实现对极低时间抖动参数的高精度测量;光外差、光学互相关等光学测量方法存在着系统复杂的缺点,并且对参考源和被测源的要求较高。为了测量阿秒级别的时间抖动,本文研究了一种高精度、无参考源的时间抖动测量方法,该方法主要基于长光纤延迟线和光载波干涉技术实现对时间抖动的超高精度测量,在满足较高测量精度的前提下无需两个相似待测源,极大降低了测量系统的复杂程度。然后,优化了测量系统结构,解释了光纤延迟线体系中伪像峰机理,并提出了二次差频梳齿模型。系统仿真测得100 MHz重频激光器在其100次谐波点10 GHz处、频偏10 MHz时的噪声基底为3.29×10-13 fs2/Hz(等同于-211 dBc/Hz),从10 kHz到10 MHz总的均方根时间抖动为535 as。实验结果表明,此方法在超低时间抖动测量方面具有明显优势,作为一种便捷、高效的时间抖动测量方法,可以应用于被动锁模激光器、光频梳、超连续谱等不同待测源。Timing jitter is a key parameter of low-noise systems,including optical frequency combs and low-noise laser microwave photon radar systems.Consequently,precisely measuring its values is quite important.The traditional direct detection method is limited by the floor noise of the microwave oscillator or photodetector noise,and its measurement accuracy is relatively low.Optical measuring methods,such as optical heterodyne and optical cross-correlation methods,are very complicated and have relatively high requirements on both reference and measured sources.This study presents a method to measure timing jitter with high precision without using a reference source,thereby overcoming some deficiencies of traditional methods.Based on long fiber delay line technology and optical carrier frequency interference,an attempt is made to realize ultra-high precision for measuring timing jitter.Results from the simulated system show that the noise base of a 10-MHz laser is 3.29×10-13 fs2/Hz(equivalent to-211 dBc/Hz)when the frequency deviation is 100 MHz at its 100th power harmonic point 10 GHz,and the total root mean square timing jitter from 10 kHz to 10 MHz is 535 as,which has an obvious advantage for ultra-low timing jitter measurement.This measurement method is a convenient,high-efficiency method that can be applied to different measured sources,such as passively mode-locked lasers,optical frequency combs,and super-continuum spectra.

关 键 词：时间抖动 锁模激光器 光纤 光外差 频域分析 

分 类 号：TN249[电子电信—物理电子学]