Widely tunable mode-hop free external cavity quantum cascade laser for high resolution spectroscopic applications

Abstract

An external cavity (EC) quantum cascade laser (QCL) configuration with the thermoelectrically cooled gain medium fabricated using a bound-to-continuum design and operating in continuous wave at ∼ 5.2 μm is reported. The EC architecture employs a piezo-activated cavity mode tracking system for mode-hop free operation suitable for high resolution spectroscopic applications and multiple species trace-gas detection. The performance of the EC-QCL exhibits coarse single mode tuning over 35 cm-1 and a continuous mode-hop free fine tuning range of ∼ 1.2 cm-1. © Springer-Verlag 2005.