A dual chirped-pulse electro-optical frequency comb method for simultaneous molecular spectroscopy and dynamics studies: Formic acid in the THz region

TL;DR

This paper introduces a dual chirped-pulse electro-optical frequency comb technique that enables simultaneous molecular spectroscopy and dynamics studies in the THz region, providing detailed spectral and temporal information.

Contribution

The paper presents a novel dual comb method based on chirped pulses for concurrent acquisition of spectral and dynamic molecular data in the THz range.

Findings

Successfully measured formic acid spectra in 10-20 cm^-1 range

Captured temporally magnified rapid passage signals

Demonstrated applicability across various spectral regions

Abstract

An electro-optic dual comb system based on chirped-pulse waveforms is used to simultaneously acquire temporally magnified rapid passage signals and normal spectral line shapes from the back-transformation to the time domain. Multi-heterodyne THz wave generation and detection is performed with the difference frequency mixing of two free-running lasers. The method is used to obtain THz spectra of formic acid in the 10 cm-1 to 20 cm-1 (300 GHz to 600 GHz) region over a range of pressures. The method is widely applicable across other spectral regions for investigations of the transient dynamics and spectroscopy of molecular systems.