Single-Mode Tunable Interband Cascade Laser Emitting at 3.4 μm With a Wide Tuning Range Over 100 nm

Abstract

We report a widely tunable monolithically integrated V-coupled cavity interband cascade laser (ICL) emitting near <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$3.4~\mu \text{m}$ </tex-math></inline-formula> . The mode selection is achieved using a half-wave V-coupler designed for the ICL in the mid-infrared range without any grating. The side-mode suppression ratio is demonstrated up to 35.7 dB. In the heat-sink temperature range from 130 K to 140 K, single-mode wavelength tuning range of over 100 nm from 3329.9 nm to 3431.3 nm has been attained by adjusting both current and temperature. These results show that the V-coupled cavity ICLs are very promising for multi-species trace gas absorption spectroscopy with a high sensitivity.