A low-noise, high-SNR balanced homodyne detector for the bright squeezed state measurement in 1–100 kHz range  

作　　者：Jin-Rong Wang Qing-Wei Wang Long Tian Jing Su Yao-Hui Zheng 王锦荣;王庆伟;田龙;苏静;郑耀辉(State Key Laboratory of Quantum Optics and Quantum Optics Devices,Institute of Opto-Electronics,Shanxi University,Taiyuan 030006,China;Collaborative Innovation Center of Extreme Optics,Shanxi University,Taiyuan 030006,China)

机构地区：[1]State Key Laboratory of Quantum Optics and Quantum Optics Devices,Institute of Opto-Electronics,Shanxi University,Taiyuan 030006,China [2]Collaborative Innovation Center of Extreme Optics,Shanxi University,Taiyuan 030006,China

出　　处：《Chinese Physics B》2020年第3期215-220,共6页中国物理B（英文版）

基　　金：Project supported by the National Natural Science Foundation of China(Grant Nos.11654002,61575114,11874250,and 11804207);the National Key Research and Development Program of China(Grant No.2016YFA0301401);the Program for Sanjin Scholar of Shanxi Province,China;the Program for Outstanding Innovative Teams of Higher Learning Institutions of Shanxi,China;the Fund for Shanxi“1331 Project”Key Subjects Construction,China;Key Research and Development Projects of Shanxi Province,China(Grant No.201903D111001)。

摘　　要：We report a low-noise, high-signal-to-noise-ratio(SNR) balanced homodyne detector based on the standard transimpedance amplifier circuit and the inductance and capacitance combination for the measurement of the bright squeezed state in the range from 1 kHz to 100 kHz. A capacitance is mounted at the input end of the AC branch to prevent the DC photocurrent from entering the AC branch and avoid AC branch saturation. By adding a switch at the DC branch,the DC branch can be flexibly turned on and off on different occasions. When the switch is on, the DC output provides a monitor signal for laser beam alignment. When the switch is off, the electronic noise of the AC branch is greatly reduced at audio-frequency band due to immunity to the impedance of the DC branch, hence the SNR of the AC branch is significantly improved. As a result, the electronic noise of the AC branch is close to -125 dBm, and the maximum SNR of the AC branch is 48 dB with the incident power of 8 mW in the range from 1 kHz to 100 kHz. The developed photodetector paves a path for measuring the bright squeezed state at audio-frequency band.We report a low-noise, high-signal-to-noise-ratio(SNR) balanced homodyne detector based on the standard transimpedance amplifier circuit and the inductance and capacitance combination for the measurement of the bright squeezed state in the range from 1 kHz to 100 kHz. A capacitance is mounted at the input end of the AC branch to prevent the DC photocurrent from entering the AC branch and avoid AC branch saturation. By adding a switch at the DC branch,the DC branch can be flexibly turned on and off on different occasions. When the switch is on, the DC output provides a monitor signal for laser beam alignment. When the switch is off, the electronic noise of the AC branch is greatly reduced at audio-frequency band due to immunity to the impedance of the DC branch, hence the SNR of the AC branch is significantly improved. As a result, the electronic noise of the AC branch is close to -125 dBm, and the maximum SNR of the AC branch is 48 dB with the incident power of 8 mW in the range from 1 kHz to 100 kHz. The developed photodetector paves a path for measuring the bright squeezed state at audio-frequency band.

关 键 词：quantum optics PHOTODETECTOR LOW-NOISE audio band 

分 类 号：O431.2[机械工程—光学工程] TN15[理学—光学]