Independent high-purity photons created in domain-engineered crystals

TL;DR

This paper introduces a novel domain-engineering method for nonlinear crystals that produces high-purity, independently heralded photon pairs at telecom wavelengths, enhancing quantum photonic technology capabilities.

Contribution

The work presents a new domain-engineering technique for nonlinear crystals to generate high-purity, independently heralded photon pairs without the need for spectral filtering.

Findings

Achieved high heralding efficiency and brightness

Produced spectral purity without filtering

Generated telecom-wavelength photon pairs independently heralded

Abstract

Advanced photonic quantum technology relies on multi-photon interference which requires bright sources of high-purity single photons. Here, we implement a novel domain-engineering technique for tailoring the nonlinearity of a parametric down-conversion crystal. We create pairs of independently-heralded telecom-wavelength photons and achieve high heralding, brightness and spectral purities without filtering.