Interband cascade lasers for sensing operating in continuous wave mode at room temperature

Abstract

The 3 to 4 µm wavelength range is of special interest for sensing applications. Interband cascade lasers (ICLs) have proven to be very attractive lasers for this range. We report on design optimizations of ICLs to reduce the dissipated threshold power with the aim to improve the high temperature performance. Distributed feedback ICLs with vertical sidewall gratings show single mode emission and they operate in continuous wave mode at room temperature. The devices exhibit side-mode suppression ratios of ~25 dB and typical fine tuning rates of 0.09 nm/mA and 0.3 nm/K. Therewith, the presented devices are very suitable for hydrocarbon sensing applications.