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arXiv · 1904.03415

Lock-in-detection dual-comb spectroscopy

Hidenori Koresawa·Kyuki Shibuya·Takeo Minamikawa·Akifumi Asahara·Ryo Oe·Takahiko Mizuno·Masatomo Yamagiwa·Yasuhiro Mizutani·Tetsuo Iwata·Hirotsugu Yamamoto·Kaoru Minoshima·Takeshi Yasui
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Abstract

Dual-comb spectroscopy (DCS) is useful for gas spectroscopy due to high potential of optical frequency comb (OFC). However, fast Fourier transform (FFT) calculation of a huge amount of temporal data spends significantly longer time than the acquisition time of an interferogram. In this article, we demonstrate frequency-domain DCS by a combination of DCS with lock-in detection, namely LID-DCS. LID-DCS directly extracts an arbitrary OFC mode from a vast number of OFC modes without the need for FFT calculation. Usefulness of LID-DCS is demonstrated in rapid monitoring of transient signal change and spectroscopy of hydrogen cyanide gas.

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Hidenori Koresawa, Kyuki Shibuya, Takeo Minamikawa, Akifumi Asahara, Ryo Oe, Takahiko Mizuno, Masatomo Yamagiwa, Yasuhiro Mizutani, Tetsuo Iwata, Hirotsugu Yamamoto, Kaoru Minoshima, Takeshi Yasui. 2019-04-06. Lock-in-detection dual-comb spectroscopy. https://doi.org/10.1364/osac.2.001998

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