Rigorous criterion for characterizing correlated multiphoton emissions

TL;DR

This paper introduces a rigorous and practical criterion for detecting correlated multi-photon emissions in quantum optical systems, improving upon existing methods by better characterizing photon correlations in quantum information applications.

Contribution

It proposes a new, easy-to-implement criterion based on wavefunction collapse for accurately identifying multi-photon correlations, addressing limitations of current measurement techniques.

Findings

The criterion is robust against experimental limitations.

It effectively detects correlated multi-photon emissions in anharmonic optical systems.

The approach enhances the characterization of photon correlations for quantum information processing.

Abstract

Strong correlation of photons, particularly in the single-photon regime, has recently been exploited for various applications in quantum information processing. Existing correlation measurements, however, do not fully characterize multi-photon correlation in a relevant context and may pose limitations in practical situations. We propose a conceptually rigorous, but easy-to-implement, criterion for detecting correlated multi-photon emission out of a quantum optical system, drawn from the context of wavefunction collapse. We illustrate the robustness of our approach against experimental limitations by considering an anharmonic optical system.