Mid-infrared frequency combs

TL;DR

Mid-infrared frequency combs are emerging tools that extend the capabilities of laser frequency combs into the mid-infrared spectrum, enabling advanced molecular spectroscopy and broadening scientific applications.

Contribution

This paper reviews recent developments in mid-infrared frequency comb generation techniques and their potential to revolutionize molecular spectroscopy and related fields.

Findings

New mid-infrared comb sources based on novel laser media

Enhanced precision and sensitivity in molecular spectroscopy

Potential for new scientific discoveries in molecular sciences

Abstract

Laser frequency combs are coherent light sources that emit a broad spectrum consisting of discrete, evenly spaced narrow lines, each having an absolute frequency measurable within the accuracy of an atomic clock. Their development, a decade ago, in the near-infrared and visible domains has revolutionized frequency metrology with numerous windfalls into other fields such as astronomy or attosecond science. Extension of frequency comb techniques to the mid-infrared spectral region is now under exploration. Versatile mid-infrared frequency comb generators, based on novel laser gain media, nonlinear frequency conversion or microresonators, promise to significantly expand the tree of applications of frequency combs. In particular, novel approaches to molecular spectroscopy in the fingerprint region, with dramatically improved precision, sensitivity, recording time and/or spectral bandwidth may spark off new discoveries in the various fields relevant to molecular sciences.