An Acoustic Sensor Based on Active Fiber Fabry–Pérot Microcavities

Sensors

Ming-Zhong Ai¹  Chuan-Feng Li¹  Xin-Xia Gao¹  Yun-Feng Huang¹  Jin-Ming Cui¹  Guang-Can Guo¹ 

[1] CAS Key Laboratory of Quantum Information, University of Science and Technology of China, Hefei 230026, China;

关键词: acoustic sensor;    fiber Fabry–Pérot cavity;    micro-laser;   

DOI  :  10.3390/s20205760

来源: DOAJ

【 摘 要 】

We demonstrate an active acoustic sensor based on a high-finesse fiber Fabry–Pérot micro-cavity with a gain medium. The sensor is a compacted device lasing around 1535 nm by external optical pumping. The acoustic pressure acting on the sensor disturbs the emitted laser frequency, which is subsequently transformed to beat signals through a delay-arm interferometer, and directly detected by a photo-detector. In this configuration, the sensing device exhibits a high sensitivity of 2.6 V/Pa and a noise equivalent acoustic signal level of 230 $\mathsf{\mu }\mathrm{Pa}/{\mathrm{Hz}}^{1/2}$ at a frequency of 4 kHz. Experimental results provide a wide frequency response from 100 Hz to 18 kHz. As the sensor works at communication wavelength and the output laser can be electrically tuned in the 10 nm range, a multi-sensor network can be easily constructed with the dense wavelength division multiplexing devices. Extra lasers or demodulators are unnecessary thus the proposed sensor is low cost and easy fabrication. The proposed sensor shows broad applications prospect in remote oil and gas leakage exploration, photo-acoustic spectrum detection, and sound source location.

【 授权许可】

Unknown