Using a DS-DBR laser for widely tunable near-infrared cavity ring-down spectroscopy

作者：Whittaker K E; Ciaffoni L; Hancock G; Hurst P L; Peverall R; Ritchie G A D^*

来源：Applied Physics B: Lasers and Optics , 2014, 116(1): 157-168.

DOI：10.1007/s00340-013-5667-z

Studies into the suitability of a novel, widely tunable telecom L-band (1,563-1,613 nm) digital supermode distributed Bragg reflector (DS-DBR) laser for cavity ring-down spectroscopy (CRDS) are presented. The spectrometer comprised of a 36.6 cm long linear cavity with ring-down times varying between 19-26 mu s across the 50 nm DS-DBR wavelength range due to changes in the cavity mirror reflectivities with wavelength. The potential of such a broadband, high-resolution CRD spectrometer was illustrated by investigating several transitions of CO2 in air, a 5 % calibrated mixture and breath samples. Allan variance measurements at a single wavelength indicated an optimal minimum detectable absorption coefficient (alpha (min)) of 3 x 10(-10) cm(-1) over 20 s.

• 出版日期2014-7