Tensor-network approach to compute genuine multisite entanglement in infinite quantum spin chains

TL;DR

This paper introduces a tensor-network based method to compute genuine multisite entanglement in infinite quantum spin chains, enabling analysis of ground states for systems with spin-1/2 and spin-1 particles.

Contribution

It develops a novel approach combining infinite tensor networks and the geometric measure to quantify multisite entanglement in the thermodynamic limit.

Findings

Successfully computes genuine multisite entanglement in infinite spin chains.

Applies method to systems with both spin-1/2 and spin-1 particles.

Provides a framework for analyzing entanglement in large quantum many-body systems.

Abstract

We devise a method based on the tensor-network formalism to calculate genuine multisite entanglement in ground states of infinite spin chains containing spin-1/2 or spin-1 quantum particles. The ground state is obtained by employing an infinite time-evolving block decimation method acting upon an initial matrix product state for the infinite spin system. We explicitly show how such infinite matrix product states with translational invariance provide a natural framework to derive the generalized geometric measure, a computable measure of genuine multisite entanglement, in the thermodynamic limit of quantum many-body systems with both spin-1/2 and higher-spin particles.