Effect of the heralding detector properties on the conditional generation of single-photon states

TL;DR

This paper examines how the properties of heralding detectors influence the quality and efficiency of conditional single-photon state generation, comparing conventional on/off detectors with photon-number resolving detectors.

Contribution

It provides a theoretical analysis of detector effects on single-photon generation and compares two detector types in this context.

Findings

Detector efficiency impacts state fidelity and rate.

Photon-number resolution improves state quality.

Theoretical framework connects detector properties with measurement outcomes.

Abstract

Single-photons play an important role in emerging quantum technologies and information processing. An efficient generation technique consists in preparing such states via a conditional measurement on photon-number correlated beams: the detection of a single-photon on one of the beam can herald the generation of a single-photon state on the other one. Such scheme strongly depends on the heralding detector properties, such as its quantum efficiency, noise or photon-number resolution ability. These parameters affect the preparation rate and the fidelity of the generated state. After reviewing the theoretical description of optical detectors and conditional measurements, and how both are here connected, we evaluate the effects of these properties and compare two kind of devices, a conventional on/off detector and a two-channel detector with photon-number resolution ability.