Exceptional-Point-Induced Nonequilibrium Entanglement Dynamics in Bosonic Networks

TL;DR

This paper explores how exceptional points in non-Hermitian bosonic networks can be used to control and enhance multimode entanglement, revealing spectral transitions and new entanglement dynamics.

Contribution

It introduces a framework for understanding EP-induced entanglement dynamics in bosonic chains, highlighting the role of higher-order EPs in amplifying quantum correlations.

Findings

Higher-order EPs significantly boost multimode entanglement.

Spectral transitions correspond to different entanglement behaviors.

Non-Hermitian physics offers new avenues for quantum control.

Abstract

Exceptional points (EPs), arising in non-Hermitian systems, have garnered significant attention in recent years, enabling advancements in sensing, wave manipulation, and mode selectivity. However, their role in quantum systems, particularly in influencing quantum correlations, remains underexplored. In this work, we investigate how EPs control multimode entanglement in bosonic chains. Using a Bogoliubov-de Gennes (BdG) framework to describe the Heisenberg equations, we identify EPs of varying orders and uncover spectral transitions between purely real, purely imaginary, and mixed eigenvalue spectra. These spectral regions, divided by EPs, correspond to three distinct entanglement dynamics: oscillatory, exponential, and hybrid. Remarkably, we demonstrate that higher-order EPs, realized by non-integer-pi hopping phases or nonuniform interaction strengths, significantly enhance the degree of multimode entanglement compared to second-order EPs. Our findings provide a pathway to leveraging EPs for entanglement control and exhibit the potential of non-Hermitian physics in advancing quantum technologies.