Triggerless data acquisition in asynchronous optical-sampling terahertz time-domain spectroscopy based on a dual-comb system

Makoto Okano, Shinichi Watanabe

Research output: Contribution to journalArticlepeer-review

Abstract

By using two mutually phase-locked optical frequency combs with slightly different repetition rates, we demonstrate asynchronous optical-sampling terahertz time-domain spectroscopy (ASOPS THz-TDS) without using any trigger signals or optical delay lines. Due to a tight stabilization of the repetition frequencies, it was possible to accumulate the data over 48 minutes in a triggerless manner without signal degradation. The fractional frequency stability of the measured terahertz signal is evaluated to be ∼8.0 × 10-17 after 730 s. The frequency accuracy of the obtained terahertz spectrum is ensured by phase-locking the two frequency combs to a frequency standard. To clarify the performance of our system, we characterized the absorption line of water vapor around 0.557 THz. The good agreement of the measured center frequency and linewidth with the values predicted from the HITRAN database verifies the suitability of our ASOPS THz-TDS system for precise measurements.

Original languageEnglish
Pages (from-to)39613-39623
Number of pages11
JournalOptics Express
Volume30
Issue number22
DOIs
Publication statusPublished - 2022 Oct 24

ASJC Scopus subject areas

  • Atomic and Molecular Physics, and Optics

Fingerprint

Dive into the research topics of 'Triggerless data acquisition in asynchronous optical-sampling terahertz time-domain spectroscopy based on a dual-comb system'. Together they form a unique fingerprint.

Cite this