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arXiv · 2105.06527

Time-resolved dual-comb spectroscopy with a single electro-optic modulator

Jeong Hyun Huh·Zaijun Chen·Edoardo Vicentini·Theodor W. Hänsch·Nathalie Picqué
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Abstract

Time-resolved near-infrared absorption spectroscopy of single non-repeatable transient events is performed at high spectral resolution with a dual-comb interferometer using a continuous-wave laser followed by a single electro-optic amplitude modulator. By sharing high-speed electrical/optical components, our spectrometer greatly simplifies the implementation of dual-comb spectroscopy and it offers a high mutual coherence time, measured up to 50-s, without any active stabilization system and/or data processing. The time resolution, which can be reconfigured a posteriori, is as short 100 microseconds in our experimental demonstration. For a span of 36 GHz, the mean signal-to-noise ratio of 80, at 100-MHz spectral resolution and 100-microsecond measurement time, enables the precise determination of the parameters of rovibrational lines, including intensity or concentration.

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Jeong Hyun Huh, Zaijun Chen, Edoardo Vicentini, Theodor W. Hänsch, Nathalie Picqué. 2021-05-13. Time-resolved dual-comb spectroscopy with a single electro-optic modulator. https://doi.org/10.1364/ol.431451

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