Laser absorption spectroscopy (LAS) in the mid-infrared region offers a promising new
effective technique for the quantitative analysis of trace gases in human breath. LAS enables …

Recent years have shown the importance of tunable semiconductor lasers in optical
sensing. We describe the status quo concerning DFB laser diodes between 760 nm and …

Laser spectroscopy outperforms electrochemical and semiconductor gas sensors in
selectivity and environmental survivability. However, the performance of the state-of-the-art …

Photoacoustic spectroscopy (PAS) based gas sensors with high sensitivity, wide dynamic
range, low cost, and small footprint are desirable in energy, environment, safety, and public …

Quantum cascade (QC) lasers are virtually ideal mid-infrared sources for trace gas
monitoring. They can be fabricated to operate at any of a very wide range of wavelengths …

We review our recent results in development of high-precision laser spectroscopic
instrumentation using midinfrared quantum cascade lasers (QCLs). Some of these …

We have developed and demonstrated a high-sensitivity trace gas instrument employing two
mid-infrared quantum cascade lasers and an astigmatic Herriott sample cell with up to a …

We present a new approach to the measurement of stable isotopic ratios of carbon dioxide
using a near-room-temperature pulsed quantum cascade laser and a spectral ratio method …

We review our recent results in development of high-precision laser spectroscopic
instrumentation using mid-infrared quantum cascade lasers, interband cascade lasers and …

Photothermal interferometry (PTI) with hollow core fibers (HCFs) have enabled highly
sensitive spectroscopic gas sensors in an all-fiber format. Here we report remarkable …