Entanglement detection in quantum materials with competing orders

TL;DR

This paper introduces a novel entanglement detection method for quantum materials with competing orders, applicable to continuous variables, and demonstrates its effectiveness in systems with ferroelectric order and light-matter interactions.

Contribution

It presents a new entanglement detection criterion based on collective excitations, applicable to continuous variables, and applies it to systems with competing orders in quantum materials.

Findings

Detection of collective entanglement from ferroelectric ordering.

Detection of entanglement from light-matter interactions.

Identification of a collective entangled phase unrelated to symmetry breaking.

Abstract

We investigate entanglement detection in quantum materials through criteria based on the simultaneous suppression of collective matter excitations. Unlike other detection schemes, these criteria can be applied to continuous and unbounded variables. By considering a system of interacting dipoles on a lattice, we show the detection of collective entanglement arising from two different physical mechanisms, namely, the ferroelectric ordering and the dressing of matter degrees of freedom by light. In the latter case, the detection shows the formation of a collective entangled phase not directly related to spontaneous symmetry breaking. These results open a new perspective for the entanglement characterization of competing orders in quantum materials, and have direct application to quantum paraelectrics with large polariton splittings.