Down-conversion source of positively spectrally correlated and decorrelated photon pairs at telecom wavelength

TL;DR

This paper experimentally characterizes a BBO-based SPDC source at 1550 nm that produces photon pairs with positive or no spectral correlations, which is significant for quantum communication and computing.

Contribution

It demonstrates a down-conversion source capable of generating positively correlated or decorrelated photon pairs at telecom wavelengths, with a novel detection approach.

Findings

Photon pairs with positive spectral correlation achieved

Spectral decorrelation demonstrated at telecom wavelength

Potential applications in quantum communication and computing

Abstract

The frequency correlation (or decorrelation) of photon pairs is of great importance in long-range quantum communications and photonic quantum computing. We experimentally characterize a spontaneous parametric down conversion (SPDC) source, based on a Beta-Barium Borate (BBO) crystal cut for type-II phase matching at 1550 nm which emits photons with the positive or no spectral correlations. Our system employs a carefully designed detection method exploiting two InGaAs detectors.