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arXiv · 2501.04874

Robust asynchronous optical sampling terahertz spectroscopy using commercially available free-running lasers

Mayuri Nakagawa·Natsuki Kanda·Hidekazu Nakamae·Hidefumi Akiyama·Ryusuke Matsunaga
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Abstract

This study presents asynchronous optical sampling (ASOPS) terahertz spectroscopy using commercially available Ti:Sapphire lasers without stabilizing repetition frequency. Our postprocessing algorithm using the multiplied repetition frequency difference as the calibration signal successfully corrected the jitter, thereby allowing broadband (2.5 THz) spectroscopy with a high spectral resolution (82 MHz). The robustness of the jitter correction based on the free-running laser setup and broadband electric circuits was rigorously examined under varying temperatures, thereby demonstrating reliable long-term operations over 60 h. This study expands the applicability of the ASOPS terahertz time-domain spectroscopy.

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Mayuri Nakagawa, Natsuki Kanda, Hidekazu Nakamae, Hidefumi Akiyama, Ryusuke Matsunaga. 2025-01-08. Robust asynchronous optical sampling terahertz spectroscopy using commercially available free-running lasers. https://doi.org/10.1364/oe.555177

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