Optimal antibunching in passive photonic devices based on coupled nonlinear resonators

TL;DR

This paper demonstrates that coupled nonlinear resonators made from passive materials can generate single photons efficiently through quantum interference and photon blockade, offering a promising approach for integrated quantum photonics.

Contribution

It introduces a novel method for single-photon generation using weakly nonlinear passive materials in coupled resonators, avoiding the need for artificial atoms or emitters.

Findings

Strong nonlinear enhancement via electromagnetic confinement enables single-photon generation.

Theoretical characterization shows high efficiency considering realistic loss and decoherence.

Compatible with current semiconductor technology and telecom wavelengths.

Abstract

We propose the use of weakly nonlinear passive materials for prospective applications in integrated quantum photonics. It is shown that strong enhancement of native optical nonlinearities by electromagnetic field confinement in photonic crystal resonators can lead to single-photon generation only exploiting the quantum interference of two coupled modes and the effect of photon blockade under resonant coherent driving. For realistic system parameters in state of the art microcavities, the efficiency of such single-photon source is theoretically characterized by means of the second-order correlation function at zero time delay as the main figure of merit, where major sources of loss and decoherence are taken into account within a standard master equation treatment. These results could stimulate the realization of integrated quantum photonic devices based on non-resonant material media, fully integrable with current semiconductor technology and matching the relevant telecom band operational wavelengths, as an alternative to single-photon nonlinear devices based on cavity-QED with artificial atoms or single atomic-like emitters.