Quantum coherence in the Dynamical Casimir Effect

TL;DR

This paper proposes using quantum coherence as a definitive indicator of quantum behavior in the Dynamical Casimir Effect, highlighting its robustness and independence from pump thresholds compared to other quantum correlations.

Contribution

It introduces quantum coherence as a new, robust measure for confirming quantum nature in the Dynamical Casimir Effect experiments, surpassing previous correlation-based methods.

Findings

Quantum coherence is a reliable indicator of quantum nature in the DCE.

Quantum coherence does not require a threshold pump amplitude.

Quantum coherence is highly robust to thermal noise.

Abstract

We propose to use quantum coherence as ultimate proof of quantum nature in the radiation that appears by means of the Dynamical Casimir Effect in experiments with superconducting microwave waveguides. We show that, unlike previously considered measurements of quantum correlations such as entanglement and discord, quantum coherence does not require a threshold value of the external pump amplitude and is highly robust to thermal noise.