Tunable optical parametric generator based on the pump spatial walk-off

TL;DR

This paper introduces a novel optical parametric generator leveraging pump beam walk-off to produce bright, tunable, and broadband signal and idler beams with high efficiency and strong correlations, enabling advanced nonlinear optical applications.

Contribution

It presents a new OPG design that exploits pump walk-off for improved beam quality, tunability, and efficiency, differing from traditional configurations.

Findings

High conversion efficiency of generated beams

Nearly single-mode spatial profile of output beams

Wide tunability and broadband operation

Abstract

We suggest a novel optical parametric generator (OPG) in which one of the down-converted beams is spontaneously generated along the Poynting vector of the pump beam. In this configuration, the generation takes advantage of the walk-off of the extraordinary pump rather than being degraded by it. As a result the generated beams, signal and idler, are bright, due to a high conversion efficiency, spatially nearly single-mode, due to the preferred direction of the Poynting vector, tuneable over a wide range of wavelengths, and broadband. The two beams are also correlated in frequency and in the photon number per pulse. Furthermore due to their thermal statistics these beams can be used as a pump to efficiently generate other nonlinear processes.