High-Power Mid-IR Few-Cycle Frequency Comb from Quadratic Solitons in an Optical Parametric Oscillator

TL;DR

This paper demonstrates a high-power, efficient mid-infrared frequency comb generated from quadratic solitons in an optical parametric oscillator operating in the simulton regime, surpassing previous sources in power, bandwidth, and efficiency.

Contribution

It introduces the use of quadratic solitons in an OPO operating in the simulton regime for high-power MIR frequency comb generation, showing improved performance over conventional methods.

Findings

Achieved 565 mW average power in the MIR range.

Demonstrated 900 nm bandwidth and 350% slope efficiency.

Showed superiority over previous MIR comb sources.

Abstract

Powerful and efficient optical frequency combs in the mid-infrared (MIR) spectral region are highly desirable for a broad range of applications. Despite extensive efforts utilizing various techniques, MIR frequency comb sources are still lacking power, efficiency, or bandwidth for many applications. Here, we report the generation of an intrinsically locked frequency comb source centered at 4.18 {\mu}m from an optical parametric oscillator (OPO) operating in the simulton regime, in which formation of purely quadratic solitons lead to enhanced performance. We show advantages of operation in the simulton regime in direct experimental comparisons to the conventional regime, which are also supported by simulation and theory. We achieve 565 mW of average power, 900 nm of instantaneous 3-dB bandwidth, 350% of slope efficiency, and 44% of conversion efficiency; a performance that is superior to previous OPO demonstrations and other sources in this wavelength range. This work opens a new avenue toward MIR frequency comb generation with high power and efficiency and suggests the great potential of soliton generation based on quadratic nonlinearity in the MIR spectral region.