Ultrastable Fiber-Based Time-Domain Balanced Homodyne Detector for Quantum Communication  

作　　者：WANG Xu-Yang BAI Zeng-Liang DU Peng-Yan LI Yong-Min PENG Kun-Chi 王旭阳;白增亮;杜鹏燕;李永民;彭堃墀(State Key Laboratory of Quantum Optics and Quantum Optics Devices,Institute of Opto-Electronics,Shanxi University,Taiyuan 030006)

机构地区：[1]State Key Laboratory of Quantum Optics and Quantum Optics Devices,Institute of Opto-Electronics,Shanxi University,Taiyuan 030006

出　　处：《Chinese Physics Letters》2012年第12期78-81,共4页中国物理快报（英文版）

基　　金：Supported by the National Natural Science Foundation of China(NSFC)(11074156);the TYAL,the National Key Basic Re-search Program of China(2010CB923101);the NSFC Project for Excellent Research Team(61121064);the Shanxi Scholarship Council of China.

摘　　要：We present an ultrastable fiber-based time-domain balanced homodyne detector which can be used for precise characterization of pulsed quantum light fields.A variable optical attenuator based on bending the fiber is utilized to compensate for the different quantum efficiencies of the photodiodes precisely,and a common mode rejection ratio of above 76 dB is achieved.The detector has a gain of 3.2μV per photon and a signal-to-noise ratio above 20 dB.Optical pulses with repetition rates up to 2 MHz can be measured with a detection efficiency of 66%.The stability of the detector is analyzed via an Allan variance measurement and the detector exhibits superior stability which enables a 100-s window for measurement without calibration.

关 键 词：QUANTUM stability PRECISE 

分 类 号：O57[理学—粒子物理与原子核物理]