Experimental Confirmation of the General Solution to the Multiple Phase Matching Problem

TL;DR

This paper experimentally confirms a general solution for multiple phase matching in nonlinear optics, demonstrating a more efficient frequency doubling device using a photonic quasicrystal and challenging conventional duty cycle practices.

Contribution

It provides the first experimental validation of a general phase matching solution using a photonic quasicrystal for multiple nonlinear processes.

Findings

The device achieved higher efficiency than periodic quasi-phase-matching counterparts.

Simple duty cycles of 100% and 0% can optimize efficiency.

Experimental confirmation of the theoretical solution was successful.

Abstract

We recently described a general solution to the phase matching problem that arises when one wishes to perform an arbitrary number of nonlinear optical processes in a single medium [PRL 95 (2005) 133901]. Here we outline in detail the implementation of the solution for a one dimensional photonic quasicrystal which acts as a simultaneous frequency doubler for three independent optical beams. We confirm this solution experimentally using an electric field poled KTiOPO$_4$ crystal. In optimizing the device, we find - contrary to common practice - that simple duty cycles of 100% and 0% may yield the highest efficiencies, and show that our device is more efficient than a comparable device based on periodic quasi-phase-matching.