# Edge states reconstruction from strong correlations in quantum spin Hall insulators

## TL;DR

This paper investigates how strong local Coulomb interactions cause edge state reconstruction in quantum spin Hall insulators, revealing that edge states undergo Mott localization before the bulk, driven by electronic correlations.

## Contribution

It demonstrates that electronic correlations induce edge reconstruction in quantum spin Hall insulators, a phenomenon driven by Mott localization of helical edge states.

## Key findings

- Edge states experience Mott localization before the bulk.
- Edge reconstruction is driven by electronic correlations.
- Topological properties explain the edge reconstruction.

## Abstract

We study quantum spin Hall insulators with local Coulomb interactions in the presence of boundaries using dynamical mean field theory. We investigate the different influence of the Coulomb interaction on the bulk and the edge states. Interestingly, we discover an edge reconstruction driven by electronic correlations. The reason is that the helical edge states experience Mott localization for an interaction strength smaller than the bulk one. We argue that the significance of this edge reconstruction can be understood by topological properties of the system characterized by a local Chern marker.