Topology and many-body localization

R. N. Bhatt, Akshay Krishna

Research output: Contribution to journalArticlepeer-review

Abstract

We discuss the problem of localization in two dimensional electron systems in the quantum Hall (single Landau level) regime. After briefly summarizing the well-studied problem of Anderson localization in the non-interacting case, we concentrate on the problem of disorder induced many-body localization (MBL) in the presence of electron–electron interactions using numerical exact diagonalization and eigenvalue spacing statistics as a function of system size. We provide evidence showing that MBL is not attainable in a single Landau level with short range (white noise) disorder in the thermodynamic limit. We then study the interplay of topology and localization, by contrasting the behavior of topological and nontopological subbands arising from a single Landau level in two models — (i) a pair of extremely flat Hofstadter bands with an optimally chosen periodic potential, and (ii) a Landau level with a split-off nontopological impurity band. Both models provide convincing evidence for the strong effect of topology on the feasibility of many-body localization as well as slow dynamics starting from a nonequilibrium state with charge imbalance.

Original languageEnglish (US)
Article number168438
JournalAnnals of Physics
DOIs
StateAccepted/In press - 2021

All Science Journal Classification (ASJC) codes

  • Physics and Astronomy(all)

Keywords

  • Disorder
  • Localization
  • Quantum Hall

Fingerprint

Dive into the research topics of 'Topology and many-body localization'. Together they form a unique fingerprint.

Cite this