A Source of Heralded Single Photon Using High Quality Factor Silicon Ring Resonators

We show generation of quantum states of light using high quality factor silicon ring resonators. Quality factors exceeding 10
⁵
are obtained via atomic-scale smoothening of the waveguides sidewalls roughness thanks to high temperature hydrogen annealing. The high quality factors yield emission of photon pairs with high rate, and we report heralding of single photons generated in our rings with values of g
⁽²⁾
(0) as low as 0.021 ± 0.003.