Ultra-high extinction ratio optical pulse generation with a thin film lithium niobate modulator for distributed acoustic sensing  

作　　者：YUAN SHEN XIAOQIAN SHU LINGMEI MA SHAOLIANG YU GENGXIN CHEN LIU LIU RENYOU GE BIGENG CHEN YUNJIANG RAO 

机构地区：[1]Research Center for Optical Fiber Sensing,Zhejiang Laboratory,Hangzhou 311100,China [2]Research Center for Intelligent Optoelectronic Computing,Zhejiang Laboratory,Hangzhou 311100,China [3]International Research Center for Advanced Photonics,College of Optical Science and Engineering,Zhejiang University,Hangzhou 310058,China [4]Fiber Optics Research Center(FORC),Key Laboratory of Optical Fiber Sensing and Communications,University of Electronic Science and Technology of China,Chengdu 611731,China

出　　处：《Photonics Research》2024年第1期40-50,共11页光子学研究（英文版）

基　　金：Center-initiated Research Project of Zhejiang Laboratory(K2022ME0AL04);National Key Research and Development Program of China(2021ZD0109904);National Natural Science Foundation of China(62105301);Key Research Project of Zhejiang Laboratory(2020ME0AD02)。

摘　　要：We experimentally demonstrate ultra-high extinction ratio(ER)optical pulse modulation with an electro-optical modulator(EOM)on thin film lithium niobate(TFLN)and its application for fiber optic distributed acoustic sensing(DAS).An interface carrier effect leading to a relaxation-tail response of TFLN EOM is discovered,which can be well addressed by a small compensation component following the main driving signal.An ultrahigh ER>50 dB is achieved by canceling out the tailed response during pulse modulation using the EOM based on a cascaded Mach–Zehnder interferometer(MZI)structure.The modulated optical_(√)pulses are then utilized as a probe light for a DAS system,showing a sensitivity up to-62.9 dB·rad∕Hz~2(7 pε/Hz)for 2-km single-mode sensing fiber.Spatial crosstalk suppression of 24.9 dB along the fiber is also obtained when the ER is improved from 20 dB to 50 dB,clearly revealing its importance to the sensing performance.

关 键 词：MODULATOR PULSE INTERFEROMETER 

分 类 号：TP212[自动化与计算机技术—检测技术与自动化装置]