All-Optical Fiber Photoacoustic Gas Sensor With Double Resonant Enhancement

作者：Zhang, Congzhe; Yang, Yuanhong; Tan, Yanzhen; Ho, Hoi Lut; Jin, Wei^*

来源：IEEE Photonics Technology Letters, 2018, 30(20): 1752-1755.

DOI：10.1109/LPT.2018.2868450

• Gas detectors
• photoacoustic spectroscopy
• optical fiber sensors
• acoustic resonators

An all-optical fiber photoacoustic gas sensor with double resonant signal enhancement is presented. The sensor uses a fiber-tip graphene nano-mechanical resonator operating at one of its resonances as the acoustic detector and a micro-acoustic resonant tube, whose resonant frequency is matched to that of the graphene resonator, as the PA gas cell. Compared with the single resonant detection with a graphene resonator, a five-fold signal enhancement is achieved. With 138-mW pump power and 1-s lock-in time constant, a noise equivalent concentration of similar to 25-ppb C2H2 is achieved, corresponding to a normalized noise equivalent absorption of 1.29 x 10(-8) cm(-1) WHz(-1/2).

• 出版日期2018-10-15
• 单位北京航空航天大学; 香港理工大学深圳研究院; 香港理工大学