Probing Genuine Multipartite Entanglement in Large Systems

TL;DR

This paper presents a new entanglement witness tailored for large many-body quantum systems, enabling better analysis of genuine multipartite entanglement using tensor network representations.

Contribution

It introduces a novel entanglement witness operator compatible with tensor network states, facilitating the study of quantum correlations in large condensed matter systems.

Findings

Successfully applied to GHZ states for validation.

Demonstrated effectiveness on a 100-spin transverse Ising model.

Provides a new tool for analyzing many-body entanglement.

Abstract

We introduce a new kind of Entanglement Witness which is appropriate for studying genuine multipartite entanglement in large systems. The witness operator has a form that fits naturally to quantum states represented by tensor networks. It opens up novel routes for investigating properties of condensed matter systems, and gives a new perspective to understand many-body quantum correlations. We illustrate the potential of this new operator with a GHZ state, and apply the method to a transverse Ising model with the well-known approach of Matrix Product States and Matrix Product Operators for a hundred spins.