Sub-part-per-trillion level detection of hydrogen fluoride by cantilever-enhanced photo-acoustic spectroscopy

TL;DR

This paper introduces a highly sensitive hydrogen fluoride detection method using cantilever-enhanced photo-acoustic spectroscopy, achieving detection limits at sub-part-per-trillion levels with high temporal resolution.

Contribution

The study demonstrates a novel, highly sensitive hydrogen fluoride sensor based on cantilever-enhanced photo-acoustic spectroscopy with unprecedented detection limits.

Findings

Detection limit of 5 parts-per-trillion in 1 second

Achieved 650 parts-per-quadrillion in 32 minutes

Normalized noise equivalent absorption coefficient of 2.7×10^{-10} Wcm^{-1} Hz^{-1/2}

Abstract

We present a highly sensitive hydrogen fluoride detector based on simple cantilever-enhanced photo-acoustic spectroscopy. A noise equivalent concentration of 5 parts-per-trillion was achieved in 1 s and 650 parts-per-quadrillion in 32 min. The limits were reached with an average optical power of 950 mW using a new continuous-wave optical parametric oscillator at 2.476 \mu m. The achieved normalized noise equivalent absorption coefficient was 2.7$\times$10$^{-10}$ Wcm$^{-1}$ Hz$^{-1/2}$.