Many-body localization phase in a spin-driven chiral multiferroic chain

TL;DR

This paper demonstrates the existence of many-body localization in a chiral multiferroic spin chain using a novel level spacing distribution approach, revealing a transition that can be controlled by electric fields.

Contribution

It introduces a new method based on the full distribution of energy level spacings to identify MBL transitions, applicable to small systems, in a model relevant for multiferroic materials.

Findings

MBL phase exists in a chiral spin chain with Dzyaloshinskii Moriya interaction.

The level spacing distribution broadens at the MBL transition point.

Electric fields can steer the multiferroic MBL phase.

Abstract

Many-body localization (MBL) is an emergent phase in correlated quantum systems with promis- ing applications, particularly in quantum information. Here, we unveil the existence and analyse this phase in a chiral multiferroic model system. Conventionally, MBL occurrence is traced via level statistics by implementing a standard finite-size scaling procedure. Here, we present an approach based on the full distribution of the ratio of adjacent energy spacings. We find a strong broadening of the histograms of counts of these level spacings directly at the transition point from MBL to the ergodic phase. The broadening signals reliably the transition point without relying on an averaging procedure. The fast convergence of the histograms even for relatively small systems allows moni- toring the MBL dynamics with much less computational effort. Numerical results are presented for a chiral spin chain with a dynamical Dzyaloshinskii Moriya (DM) interaction, an established model to describe the spin excitations in a single phase spin-driven multiferroic system. The multiferroic MBL phase is uncovered and it is shown how to steer it via electric fields.