Two-photon correlations and HOM visibility from an imperfect single-photon source

TL;DR

This paper investigates how pulse duration and frequency filtering affect the purity and two-photon interference visibility of a resonantly driven single-photon source, revealing complex dependencies beyond common assumptions.

Contribution

It provides a detailed analysis of the impact of excitation pulse duration and filtering on single-photon purity and HOM visibility, highlighting nuanced source-dependent effects.

Findings

Pulse duration significantly influences single-photon quality.

Frequency filtering can alter two-photon correlations and HOM visibility.

The relationship between two-photon component and HOM visibility is more complex than previously assumed.

Abstract

We study the single photon purity of a resonantly driven single-photon source in the realistic scenario where the excitation laser can leak into the detection path. We find that the duration of the excitation pulse strongly influences the quality of the single-photon source. We calculate the influence of this on the effective parameters describing the most relevant properties, including the two-photon component and Hong-Ou-Mandel (HOM) visibility. Furthermore, we analyze how these properties can be strongly affected by frequency filtering of the outgoing field. Our results highlight that the relation between the two-photon component of the emission and the HOM visibility is more complicated than typically assumed in the literature, and depends on the specific details of the source.