Increased pump acceptance bandwidth in spontaneous parametric downconversion process using Bragg reflection waveguides

TL;DR

This paper demonstrates how tailoring dispersion in Bragg reflection waveguides enables efficient photon pair generation over a broad pump bandwidth with narrow signal bandwidth, advancing quantum source technology.

Contribution

It introduces a novel BRW design with tailored dispersion properties to enhance pump acceptance bandwidth in spontaneous parametric downconversion.

Findings

Achieved large pump bandwidth for photon pair generation

Maintained narrow signal bandwidth in the generated photons

Proposed structure suitable for compact quantum information sources

Abstract

In this paper we show that by suitably tailoring the dispersion characteristics of a Bragg reflection waveguide (BRW) mode, it is possible to achieve efficient photon pair generation over a large pump bandwidth while maintaining narrow signal bandwidth. The structure proposed consists of a high index core BRW with a periodically poled GaN core and periodically stratified cladding made up of alternate layers of $Al_{0.02}Ga_{0.98}N$ and $Al_{0.45}Ga_{0.55}N$. Such photon-pair generators should find applications in realizing compact and stable sources for quantum information processing.