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arXiv · 1907.08007

Femtosecond imbalanced time-stretch spectroscopy for ultrafast gas detection

Zhen Zhang·Haiyun Xia·Saifen Yu·Lijie Zhao·Tianwen Wei·Manyi Li
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Abstract

Dual-comb spectroscopy is a promising method for precise optical spectrum analysis with fast data acquisition speed. However, its implementation and applications are often hindered by the complexity of optical comb systems. Here, as a compact and robust system, femtosecond imbalanced time-stretch spectroscopy (FITSS) with simple optical layout is proposed and demonstrated. The time-stretch interferometry from one femtosecond laser builds a mapping from the optical frequency domain to the radio frequency regime. In experiment, the absorption line of a hydrogen cyanide cell is encoded in the probing arm of a Mach-Zehnder interferometer (MZI). The down-converted radio frequency comb is transformed from a periodically chirped waveform, which is the interferogram of the MZI with different dispersion values on two arms. By turning the optical filter, the spectrum over a wide range is analyzed.

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Zhen Zhang, Haiyun Xia, Saifen Yu, Lijie Zhao, Tianwen Wei, Manyi Li. 2020-11-10. Femtosecond imbalanced time-stretch spectroscopy for ultrafast gas detection. https://doi.org/10.1063/1.5143790

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