Paper Title
Wavelength Modulation Spectroscopy With A Distributed Feedback, Pulsed And Continuous Wave Quantum Cascade Lasers: A Comparison

We report comparative studies of current and frequency characterization measurements performed with a distributed feedback, pulsed and continuous wave quantum cascade lasers centered at 957 cm-1 and 1760 cm-1 respectively. The frequency tuning rates were measured at different current ramp and modulation frequencies and amplitudes. The frequency tuning rate depends both on the frequencies and amplitudes of the applied current ramp and the sine modulation. We also present open path wavelength modulation spectroscopic studies with these two lasers and compare our results. Similar noise equivalent detection limits were demonstrated with both the lasers when combined with wavelength modulation spectroscopy for open path measurements. Index Terms—About Four Key Words Or Phrases In Alphabetical Order, Separated By Commas.