Doping-induced Quantum Anomalous Hall Crystals and Topological Domain Walls

Fuente: arXiv
Saved in:
Bibliographic Details
Main Authors: Gonçalves, Miguel, Lin, Shi-Zeng
Format: Preprint
Published: 2024
Subjects:
Online Access:
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1866917381047058432
author Gonçalves, Miguel
Lin, Shi-Zeng
author_facet Gonçalves, Miguel
Lin, Shi-Zeng
contents Doping carriers into a correlated quantum ground state offers a promising route to generate new quantum states. The recent advent of moiré superlattices provided a versatile platform with great tunability to explore doping physics in systems with strong interplay between strong correlation and nontrivial topology. Here we study the effect of electron doping in the quantum anomalous Hall insulator realized in TMD moiré superlatice at filling $ν=1$, which can be described by the canonical Kane-Mele-Hubbard model. By solving the Kane-Mele-Hubbard model using an unrestricted real-space Hartree-Fock method, we find that doping generates quantum anomalous Hall crystals (QAHC) and topological domain walls. In the QAHC, the doping induces skyrmion spin textures, which hosts one or two electrons in each skyrmion as in-gap states. The skyrmions crystallize into a lattice, with the lattice parameter being tunable by the density of doped electrons. Remarkably, we find that the QAHC can survive even in the limit of vanishing Kane-Mele topological gap for a significant range of fillings. Furthermore, doping can also induce domain walls separating topologically distinct domains with different electron densities, hosting chiral localized modes.
format Preprint
id arxiv_https___arxiv_org_abs_2407_12198
institution arXiv
publishDate 2024
record_format arxiv
spellingShingle Doping-induced Quantum Anomalous Hall Crystals and Topological Domain Walls
Gonçalves, Miguel
Lin, Shi-Zeng
Strongly Correlated Electrons
Mesoscale and Nanoscale Physics
Doping carriers into a correlated quantum ground state offers a promising route to generate new quantum states. The recent advent of moiré superlattices provided a versatile platform with great tunability to explore doping physics in systems with strong interplay between strong correlation and nontrivial topology. Here we study the effect of electron doping in the quantum anomalous Hall insulator realized in TMD moiré superlatice at filling $ν=1$, which can be described by the canonical Kane-Mele-Hubbard model. By solving the Kane-Mele-Hubbard model using an unrestricted real-space Hartree-Fock method, we find that doping generates quantum anomalous Hall crystals (QAHC) and topological domain walls. In the QAHC, the doping induces skyrmion spin textures, which hosts one or two electrons in each skyrmion as in-gap states. The skyrmions crystallize into a lattice, with the lattice parameter being tunable by the density of doped electrons. Remarkably, we find that the QAHC can survive even in the limit of vanishing Kane-Mele topological gap for a significant range of fillings. Furthermore, doping can also induce domain walls separating topologically distinct domains with different electron densities, hosting chiral localized modes.
title Doping-induced Quantum Anomalous Hall Crystals and Topological Domain Walls
topic Strongly Correlated Electrons
Mesoscale and Nanoscale Physics
url https://arxiv.org/abs/2407.12198