Witnessing non-classicality through large deviations in quantum optics

TL;DR

This paper introduces a thermodynamic approach to analyze non-classical correlations in quantum optics by examining fluctuations and correlations in photon counting, bridging source dynamics and output field characterization.

Contribution

It presents a novel method linking quantum trajectory thermodynamics with photon counting statistics to study non-classicality.

Findings

Provides a framework to analyze quantum properties from source dynamics.

Connects trajectory-based thermodynamics with output field measurements.

Enables investigation of quantum correlations through large deviations.

Abstract

Non-classical correlations in quantum optics as resources for quantum computation are important in the quest for highly-specialized quantum devices. The standard way to investigate such effects relies on either the characterization of the inherent features of sources and circuits or the study of the output radiation of a given optical setup. The latter approach demands an extensive description of the output fields, but often overlooks the dynamics of the sources. Conversely, the former discards most of the information about the single trajectories, which are observed in experimental measurements. In this work we provide a natural link between the two frameworks by exploiting the thermodynamics of quantum trajectories. This procedure enables investigation of the quantum properties of the photon fields from a generic source via the analysis of the fluctuations and correlations of time-integrated quantities associated with the photon counting of the emitted light.