Telecommunications-band heralded single photons from a silicon nanophotonic chip

TL;DR

This paper demonstrates a silicon nanophotonic chip capable of generating heralded single photons at telecommunications wavelengths, advancing integrated quantum photonics with high efficiency and compatibility with existing CMOS technology.

Contribution

It introduces a CMOS-compatible silicon nanophotonic device that efficiently produces heralded single photons using four-wave mixing in a coupled resonator waveguide.

Findings

Photon pairs generated at telecom wavelengths with high coincidence-to-accidental ratio

Heralded photons exhibit antibunching with g^(2)(0) = 0.19

Device demonstrates potential for integrated quantum photonic circuits

Abstract

We demonstrate heralded single photon generation in a CMOS-compatible silicon nanophotonic device. The strong modal confinement and slow group velocity provided by a coupled resonator optical waveguide (CROW) produced a large four-wave-mixing nonlinearity coefficient gamma_eff ~4100 W^-1 m^-1 at telecommunications wavelengths. Spontaneous four-wave-mixing using a degenerate pump beam at 1549.6 nm created photon pairs at 1529.5 nm and 1570.5 nm with a coincidence-to-accidental ratio exceeding 20. A photon correlation measurement of the signal (1529.5 nm) photons heralded by the detection of the idler (1570.5 nm) photons showed antibunching with g^(2)(0) = 0.19 \pm 0.03. The demonstration of a single photon source within a silicon platform holds promise for future integrated quantum photonic circuits.