Bragg reflection waveguide as a source of wavelength-multiplexed polarization-entangled photon pairs

TL;DR

This paper proposes a highly efficient, integrated semiconductor waveguide source for polarization-entangled photon pairs with ultra-large bandwidth, suitable for multi-user quantum key distribution systems.

Contribution

It introduces a novel design of a semiconductor Bragg reflection waveguide for generating polarization-entangled photon pairs with large bandwidth, advancing integrated quantum photonics.

Findings

High efficiency in photon pair generation

Ultra-large bandwidth of entangled photons

Potential application in multi-user quantum key distribution

Abstract

We put forward a new highly efficient source of paired photons entangled in polarization with an ultra-large bandwidth. The photons are generated by means of a conveniently designed spontaneous parametric down-conversion process in a semiconductor type-II Bragg reflection waveguide. The proposed scheme aims at being a key element of an integrated source of polarization-entangled photon pairs highly suitable for its use in a multi-user quantum-key-distribution system.