Chip-based array of near-identical, pure, heralded single-photon sources

Abstract

Interference between independent single photons is perhaps the most\nfundamental interaction in quantum optics. It has become increasingly important\nas a tool for optical quantum information science, as one of the rudimentary\nquantum operations, together with photon detection, for generating entanglement\nbetween non-interacting particles. Despite this, demonstrations of large-scale\nphotonic networks involving more than two independent sources of quantum light\nhave been limited due to the difficulty in constructing large arrays of\nhigh-quality single photon sources. Here, we solve the key challenge, reporting\na novel array of more than eighteen near-identical, low-loss, high-purity,\nheralded single photon sources achieved using spontaneous four-wave mixing\n(SFWM) on a silica chip. We verify source quality through a series of heralded\nHong-Ou-Mandel experiments, and further report the experimental three-photon\nextension of the entire Hong-Ou-Mandel interference curves, which map out the\ninterference landscape between three independent single photon sources for the\nfirst time.\n