An all-silicon single-photon source by unconventional photon blockade

TL;DR

This paper introduces an all-silicon single-photon source using unconventional photon blockade, leveraging quantum interference and third-order nonlinearity in coupled cavities, enabling low-power, compact, and integrated quantum light sources.

Contribution

It presents a novel all-silicon device employing quantum interference and third-order nonlinearity for single-photon generation, outperforming existing parametric methods in power and size.

Findings

Demonstrates reliable pulsed operation protocol

Achieves antibunched radiation at low input powers

Proposes implementation in standard silicon photonic circuits

Abstract

The lack of suitable quantum emitters in silicon and silicon-based materials has prevented the realization of room temperature, compact, stable, and integrated sources of single photons in a scalable on-chip architecture, so far. Current approaches rely on exploiting the enhanced optical nonlinearity of silicon through light confinement or slow-light propagation, and are based on parametric processes that typically require substantial input energy and spatial footprint to reach a reasonable output yield. Here we propose an alternative all-silicon device that employs a different paradigm, namely the interplay between quantum interference and the third-order intrinsic nonlinearity in a system of two coupled optical cavities. This unconventional photon blockade allows to produce antibunched radiation at extremely low input powers. We demonstrate a reliable protocol to operate this mechanism under pulsed optical excitation, as required for device applications, thus implementing a true single-photon source. We finally propose a state-of-art implementation in a standard silicon-based photonic crystal integrated circuit that outperforms existing parametric devices either in input power or footprint area.