Single-Wavelength InGaAs/AlAs(Sb) Quantum Cascade Lasers

Conference: IPRM 2011 - 23th International Conference on Indium Phosphide and Related Materials
05/22/2011 - 05/26/2011 at Berlin, Germany

Proceedings: IPRM 2011

Pages: 2Language: englishTyp: PDF

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Authors:
Slight, Thomas; McKee, Andrew (Compound Semiconductor Technologies Global Ltd, Hamilton International Park, Hamilton G72 0BN, UK)
Slight, Thomas; Ironside, Charles (School of Engineering, University of Glasgow, Glasgow G12 8LT, UK)
Phelan, Richard; Kelly, Brian (Eblana Photonics, Trinity College Enterprise Centre, Pearse Street, Dublin 2, Ireland)
Revin, Dmitry; Cockburn, John (Department of Physics and Astronomy, University of Sheffield, Sheffield S3 7RH, UK)

Abstract:
Recently, significant progress has been made in the development of short-wavelength quantum-cascade lasers (QCLs) emitting in the 3-4 µm wavelength range, where many molecular species of interest have their strongest rotational-vibrational absorption bands. A laser designed for gas sensing applications must have a narrow spectral width in order to differentiate between the fine features of the unique absorption fingerprint of the gas. Using a distributed-feedback (DFB) design, single-wavelength operation is achieved with a first order lateral grating etched in the same step as the laser cavity. Driven pulsed at a temperature of 303 K, emission was at a wavelength of 3.35 µm with a side mode suppression ratio (SMSR) of 24 dB. In the discrete-mode (DM) design index perturbations were introduced in to the laser cavity. The features modify the Fabry-Pérot (FP) cavity loss spectrum such that lasing is in a single FP mode. Driven pulsed at a temperature of 300 K, emission was at wavelength of 3.31 µm with a SMSR of 25 dB.