Thermodynamic Signatures of Genuinely Multipartite Entanglement

TL;DR

This paper introduces thermodynamic quantities based on energy differences that serve as signatures of genuine multipartite entanglement, providing a new way to measure and distinguish different classes of entangled states.

Contribution

It proposes energy-based thermodynamic measures for genuine multipartite entanglement, extending thermodynamic-entanglement connections and enabling classification of entanglement types.

Findings

Thermodynamic measures can faithfully detect genuine multipartite entanglement.

These measures distinguish different classes of entangled states.

The approach generalizes to characterize $k$-nonseparability in multipartite systems.

Abstract

Theory of bipartite entanglement shares profound similarities with thermodynamics. In this letter we extend this connection to multipartite quantum systems where entanglement appears in different forms with genuine entanglement being the most exotic one. We propose thermodynamic quantities that capture signature of genuineness in multipartite entangled states. Instead of entropy, these quantities are defined in terms of energy -- particularly the difference between global and local extractable works (ergotropies) that can be stored in quantum batteries. Some of these quantities suffice as faithful measures of genuineness and to some extent distinguish different classes of genuinely entangled states. Along with scrutinizing properties of these measures we compare them with the other existing genuine measures, and argue that they can serve the purpose in a better sense. Furthermore, generality of our approach allows to define suitable functions of ergotropies capturing the signature of $k$-nonseparability that characterizes qualitatively different manifestations of entanglement in multipartite systems.