Entanglement dynamics and phase transitions of the Floquet cluster spin chain

TL;DR

This paper studies the entanglement dynamics and phase transitions in a Floquet-driven cluster spin chain, revealing nonthermal phases with magnetic order and dynamical phase transitions between different entanglement regimes.

Contribution

It introduces a detailed analysis of entanglement and phase transitions in Floquet cluster chains, including both integrable and interacting cases, highlighting nonthermal phases with magnetic order.

Findings

Identification of dynamical phase transitions in entanglement properties.

Discovery of nonergodic phases with persistent magnetic order.

Comparison between integrable and interacting Floquet systems.

Abstract

Cluster states were introduced in the context of measurement based quantum computing. In one dimension, the cluster Hamiltonian possesses topologically protected states. We investigate the Floquet dynamics of the cluster spin chain in an external field, interacting with a particle. We explore the entanglement properties of the topological and magnetic phases, first in the integrable spin lattice case, and then in the interacting quantum walk case. We find, in addition to thermalization, dynamical phase transitions separating low- and high-entanglement nonthermal states, reminiscent of the ones present in the integrable case, but differing in their magnetic properties. The nonergodic phases are characterized by the emergence of magnetic order, persistent at long times.