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Updated: Aug 9, 2025

Characterizing Far-infrared Laser Emissions and the Measurement of Their Frequencies
Published on: December 18, 2015
Tunable dual optical frequency comb at 2 μm for CO2 sensing
Abstract:
In this article, we demonstrate a dual frequency comb (DFC) based on the gain-switching of mutually injection-locked semiconductor lasers in the 2 μm wavelength region with a tunable free spectral range (FSR) between 500 MHz and 3 GHz. Through the down-conversion process enabled by DFCs, the beating spectra of the optical frequency combs were captured in a 15 MHz electrical bandwidth with high resolution and millisecond acquisition times. A first experimental demonstration of sensing CO2 with this architecture is also presented.
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