Linear-Optic Heralded Photon Source

TL;DR

This paper introduces a heralded photon source using only linear optics and weak coherent states, achieving sub-Poissonian photon statistics and wide spectral tunability suitable for quantum communication.

Contribution

It demonstrates a novel linear-optic method for heralded photon generation with sub-Poissonian statistics and broad tunability, avoiding phase-matching constraints of traditional sources.

Findings

Second-order correlation function $g^2(0)=0.556$ indicating sub-Poissonian statistics

100-nm spectral tunability in telecom bands

Comparable yield to spontaneous parametric down-conversion sources

Abstract

We present a Heralded Photon Source based only on linear optics and weak coherent states. By time-tuning a Hong-Ou-Mandel interferometer fed with frequency-displaced coherent states, the output photons can be synchronously heralded following sub-Poisson statistics, which is indicated by the second-order correlation function ($g^2\left(0\right)=0.556$). The absence of phase-matching restrictions makes the source widely tunable, with 100-nm spectral tunability on the telecom bands. The technique presents yield comparable to state-of-the-art spontaneous parametric down-conversion-based sources, with high coherence and fiber-optic quantum communication compatibility.