Flexible terahertz opto-electronic frequency comb light source tunable over 3.5 THz

TL;DR

This paper presents a tunable terahertz frequency comb source with adjustable frequency range, line number, and spacing, achieved through near-infrared lasers, phase modulation, and opto-electronic conversion, with high-resolution characterization.

Contribution

It introduces a flexible, tunable THz frequency comb source using a novel combination of laser diodes, phase modulation, and opto-electronic conversion techniques.

Findings

THz comb lines are < 10 MHz wide.

The comb is tunable over 3.5 THz.

High-resolution characterization confirms comb line stability.

Abstract

We demonstrate a terahertz (THz) frequency comb that is flexible in terms of its frequency range and the number and spacing of comb lines. We use a combination of near-infrared laser diodes, phase modulation and opto-electronic frequency conversion. The THz comb lines are characterized to be < 10 MHz by resolving the pressure dependent collisional broadening of an ammonia molecule rotational mode.