Multipartite Entanglement in Non-Equilibrium Quantum Phase Transition in a Collective Atomic System

TL;DR

This paper investigates how multipartite entanglement emerges during a non-equilibrium quantum phase transition in a driven atomic system with collective decay, revealing critical behavior linked to entanglement measures.

Contribution

It demonstrates the connection between non-equilibrium quantum phase transitions and multipartite entanglement using von Neumann entropy in a collective atomic system.

Findings

Critical behavior correlates with multipartite entanglement.

Von Neumann entropy derivative exhibits Lambda-type behavior.

Bi- and tri-partite entropies satisfy Lieb inequality.

Abstract

We study multipartite entanglement in non-equilibrium quantum phase transition (NEQPT) attainable in a coherently driven atomic ensemble undergoing collective decay. The NEQPT arises in the steady state of the system as the drive field strength is varied in comparison with the decay parameter. A close connection is observed between the critical behavior and the multi-partite entanglement in the system determined via the von Neumann entropy. The derivative of the von Neumann entropy shows Lambda-type behavior typical of the second order phase transitions. We further show that the calculated bi- and tri- partite entropies satisfy the Lieb inequality.