Unveiling the Hanbury Brown and Twiss effect through Renyi entropy correlations

TL;DR

This paper investigates the Hanbury Brown and Twiss effect using Renyi entropy, revealing how quantum and classical correlations vary with source intensity and offering new insights into the effect's nature.

Contribution

It introduces a quantum information approach to analyze correlations in thermal light, highlighting the role of Renyi mutual information and quantum discord in the effect.

Findings

Renyi mutual information matches normalized intensity correlations at low source intensity

Quantum discord is significant at low intensities but diminishes with increasing source intensity

Provides a new perspective on the quantum versus classical nature of the Hanbury Brown and Twiss effect

Abstract

Adopting a quantum information perspective, we analyse the correlations in the thermal light beams used to demonstrate the Hanbury Brown and Twiss effect. We find that the total correlations measured by the Renyi mutual information match the normalised intensity correlations in the regime of low source intensity. Genuine quantum correlations in the form of discord are relevant in such regime but get washed out with increasing source intensity. This provides a new angle on the issue about the nature--quantum versus classical--of the effect.