Many-body localization transition in a frustrated XY chain

TL;DR

This paper investigates the many-body localization transition in a frustrated XY chain with random magnetic fields, revealing how frustration and non-local interactions influence localization properties.

Contribution

It demonstrates the MBL transition in a frustrated XY chain using finite-size exact diagonalization and explains the delocalized phase via an effective non-local fermionic interaction.

Findings

Identification of MBL transition through level-spacing statistics and fractal dimensions.

Frustration induces effective non-local interactions among fermions.

Presence of a delocalized phase due to next-nearest-neighbor hopping.

Abstract

We demonstrate many-body localization (MBL) transition in a one-dimensional isotropic XY chain with a weak next-nearest-neighbor frustration in a random magnetic field. We perform finite-size exact diagonalization calculations of level-spacing statistics and fractal dimensions to characterize the MBL transition with increasing the random field amplitude. An equivalent representation of the model in terms of spinless fermions explains the presence of the delocalized phase by the appearance of an effective non-local interaction between the fermions. This interaction appears due to frustration provided by the next-nearest-neighbor hopping.