Scarred ferromagnetic phase in the long-range transverse-field Ising model

TL;DR

This paper discovers a set of special ferromagnetic states in a long-range transverse-field Ising model that lead to unique dynamical behavior, including persistent ferromagnetic order in certain initial conditions.

Contribution

It identifies and characterizes ferromagnetic scarred states in a long-range Ising model, revealing a new dynamical phase called the scarred ferromagnetic phase.

Findings

Scarred states are found in the long-range transverse-field Ising model.

Initial conditions with small magnetic domains can selectively populate scarred states.

A new dynamical phase, the scarred ferromagnetic phase, is identified.

Abstract

We report the existence of a large set of ferromagnetic scarred states in the one-dimensional transverse-field Ising model with long-range interactions, in a regime with no ferromagnetic phase at finite temperature. These scarred states are distributed over different spectral regions, surrounded by paramagnetic states. We show that simple initial conditions, consisting in a few small magnetic domains, selectively populate these scarred states. This leads to the appearance of a special dynamical phase, which we call scarred ferromagnetic phase. As a consequence, initial states with a small number of small magnetic domains evolve towards ferromagnetic equilibrium states, whereas initial states with larger domains or no magnetic structure relax to the expected thermal paramagnetic equilibrium state.