Experimental cyclic inter-conversion between Coherence and Quantum Correlations

TL;DR

This paper demonstrates an experimental scheme using linear optics to cyclically convert quantum coherence into correlations and back, revealing their fundamental connection and potential for resource flexibility in quantum technologies.

Contribution

It introduces a novel cyclic inter-conversion process between quantum coherence and correlations, experimentally validated with linear optics.

Findings

Successful experimental demonstration of coherence-correlation inter-conversion

Highlights the fundamental link between local coherence and non-classical correlations

Potential applications in quantum resource management and quantum information processing

Abstract

Quantum resource theories seek to quantify sources of non-classicality that bestow quantum technologies their operational advantage. Chief among these are studies of quantum correlations and quantum coherence. The former to isolate non-classicality in the correlations between systems, the latter to capture non-classicality of quantum superpositions within a single physical system. Here we present a scheme that cyclically inter-converts between these resources without loss. The first stage converts coherence present in an input system into correlations with an ancilla. The second stage harnesses these correlations to restore coherence on the input system by measurement of the ancilla. We experimentally demonstrate this inter-conversion process using linear optics. Our experiment highlights the connection between non-classicality of correlations and non-classicality within local quantum systems, and provides potential flexibilities in exploiting one resource to perform tasks normally associated with the other.