Computational coherent averaging for free-running dual-comb spectroscopy

TL;DR

This paper introduces a computational method for coherent averaging in free-running dual-comb spectroscopy, eliminating the need for extra hardware and enabling high-sensitivity, long-duration measurements with simplified system complexity.

Contribution

The authors develop a fully computational coherent averaging technique compatible with real-time systems, reducing hardware complexity in dual-comb spectroscopy.

Findings

Effective correction demonstrated with THz quantum cascade laser spectra

Achieves high sensitivity without additional electro-optical components

Compatible with real-time data processing architectures

Abstract

Dual-comb spectroscopy is a rapidly developing technique that enables moving parts-free, simultaneously broadband and high-resolution measurements with microseconds of acquisition time. However, for high sensitivity measurements and extended duration of operation, a coherent averaging procedure is essential. To date, most coherent averaging schemes require additional electro-optical components, which increase system complexity and cost. Instead, we propose an all-computational solution that is compatible with real-time architectures and allows for coherent averaging of spectra generated by free-running systems. The efficacy of the computational correction algorithm is demonstrated using spectra acquired with a THz quantum cascade laser-based dual-comb spectrometer.