Mid-infrared frequency comb with 6.7 W average power based on difference frequency generation

TL;DR

This paper demonstrates a high-power mid-infrared frequency comb with 6.7 W average power using difference frequency generation from an Er:fiber comb, enabling applications in broadband spectroscopy and light sources.

Contribution

The work presents a novel high-power mid-infrared frequency comb with stable phase and high beam quality based on difference frequency generation from fiber lasers.

Findings

Achieved 6.7 W average power at 2.9 μm in the idler

Generated 14.9 W in the 1.6 μm signal

Stable carrier-envelope phase and excellent beam quality

Abstract

We report on the development of a high-power mid-infrared frequency comb with 100 MHz repetition rate and 100 fs pulse duration. Difference frequency generation is realized between two branches derived from an Er:fiber comb, amplified separately in Yb:fiber and Er:fiber amplifiers. Average powers of 6.7 W and 14.9 W are generated in the 2.9 $\mu$m idler and 1.6 $\mu$m signal, respectively. With high average power, excellent beam quality, and passive carrier-envelope phase stabilization, this light source is a promising platform for generating broadband frequency combs in the far infrared, visible, and deep ultraviolet.