Three Photon Absorption in Optical Parametric Oscillators Based on OP-GaAs

TL;DR

This paper reports on the development of optical parametric oscillators based on OP-GaAs, highlighting the first singly-resonant design, the highest output power achieved, and the impact of three-photon absorption on performance.

Contribution

It introduces the first singly-resonant OP-GaAs OPO and provides a detailed analysis of three-photon absorption effects on these mid-IR light sources.

Findings

First SR OPO based on OP-GaAs demonstrated.

DR-OPO achieved highest femtosecond OP-GaAs output power.

Three-photon absorption limits the output power of the OPOs.

Abstract

We report on the first singly-resonant (SR), synchronously pumped optical parametric oscillator (OPO) based on orientation-patterned gallium arsenide (OP-GaAs). Together with a doubly resonant (DR) degenerate OPO based on the same OP-GaAs material, the output spectra cover 3 to 6 ${\mu}$m within ~3 dB of relative power. The DR-OPO has the highest output power reported to date from a femtosecond, synchronously pumped OPO based on OP-GaAs. We discovered strong three photon absorption with a coefficient of 0.35 ${\pm}$ 0.06 cm${^3}$/GW${^2}$ for our OP-GaAs sample, which limits the output power of these OPOs as mid-IR light sources. We present a detailed study of the three photon loss on the performance of both the SR and DR-OPOs, and compare them to those without this loss mechanism.