Department of Chemistry, University of Helsinki, P.O. Box 55, FI-00014, Helsinki, Finland.
Analyst. 2019 Mar 25;144(7):2291-2296. doi: 10.1039/c9an00058e.
We have improved the sensitivity of a state-of-the-art cantilever-enhanced photo-acoustic trace gas sensor by combining it with an optical power build-up cavity. The build-up cavity enhances the photo-acoustic signal by a factor of ∼100, resulting in an exceptionally good normalised noise equivalent absorption (NNEA) value of 1.75 × 10-12 W cm-1 Hz-1/2. We demonstrate the sensor platform in the 1530 nm wavelength range with a simple distributed feedback diode laser, achieving 75 ppt sensitivity for C2H2 with a 10 s integration time.
我们通过将一种最先进的悬臂梁增强光声痕量气体传感器与光学功率增强腔相结合,提高了该传感器的灵敏度。增强腔将光声信号增强了约 100 倍,从而获得了非常出色的归一化噪声等效吸收(NNEA)值 1.75×10-12 W cm-1 Hz-1/2。我们使用简单的分布式反馈二极管激光器在 1530nm 波长范围内展示了该传感器平台,在 10s 的积分时间内实现了对 C2H2 的 75ppt 灵敏度。