Microoptoelectromechanical systems-based external cavity quantum cascade lasers for real-time spectroscopy

Abstract

, "Microoptoelectromechanical systems-based external cavity quantum cascade lasers for real-time spectroscopy," Opt. Eng. 57(1), 011010 (2017), doi: 10.1117/1.OE.57.1.011010. Abstract. We report on mid-IR spectroscopic measurements performed with rapidly tunable external cavity quantum cascade lasers (EC-QCLs). Fast wavelength tuning in the external cavity is realized by a microoptoelectromechanical systems (MOEMS) grating oscillating at a resonance frequency of about 1 kHz with a deflection amplitude of up to 10 deg. The entire spectral range of the broadband QCL can therefore be covered in just 500 μs, paving the way for real-time spectroscopy in the mid-IR region. In addition to its use in spectroscopic measurements conducted in backscattering and transmission geometry, the MOEMS-based laser source is characterized regarding pulse intensity noise, wavelength reproducibility, and spectral resolution. © The Authors.Published by SPIE under a Creative Commons Attribution 3.0 Unported License. Distribution or reproduction of this work in whole or in part requires full attribution of the original publication, including its DOI.

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