Resonant and non-resonant integrated third order parametric down-conversion

TL;DR

This paper explores third order parametric down-conversion (TOPDC) in integrated photonic systems, analyzing resonant and non-resonant platforms for generating non-classical light, and predicts feasible experimental demonstrations.

Contribution

It derives equations for TOPDC rates in different platforms and compares their suitability for spontaneous and stimulated processes, guiding future experimental efforts.

Findings

Non-resonant platforms are better for spontaneous TOPDC.

Resonant platforms are more suitable for stimulated TOPDC.

Stimulated TOPDC should be observable with current technology.

Abstract

Third order parametric down-conversion describes a class of nonlinear processes in which a pump photon can be down-converted into triplets of photons. It has been identified as a source of non-classical light, with capabilities beyond those offered by better-established processes such as spontaneous four-wave mixing. Here we discuss the implementation of TOPDC in integrated photonic systems. We derive equations for the rates of TOPDC in a non-resonant (waveguide) and resonant (microring) platform, such that the scaling with experimental parameters can be plainly seen. We find that generally non-resonant platforms should be pursued for spontaneous TOPDC (SpTOPDC), whereas resonant platforms are more suitable for stimulated TOPDC (StTOPDC). We present a sample calculation for TOPDC rates in sample systems with conservative and accessible parameters. We find that StTOPDC should be observable with the current fabrication technology, and that with some progress in the design of TOPDC platforms, integrated SpTOPDC too could be demonstrated in the near term.