Single-particle spectral function of fractional quantum anomalous Hall states

Fuente: arXiv
Saved in:
Bibliographic Details
Main Authors: Pichler, Fabian, Kadow, Wilhelm, Kuhlenkamp, Clemens, Knap, Michael
Format: Preprint
Published: 2024
Subjects:
Online Access:
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1866910814581030912
author Pichler, Fabian
Kadow, Wilhelm
Kuhlenkamp, Clemens
Knap, Michael
author_facet Pichler, Fabian
Kadow, Wilhelm
Kuhlenkamp, Clemens
Knap, Michael
contents Fractional quantum Hall states are the most prominent example of states with topological order, hosting excitations with fractionalized charge. Recent experiments in twisted $\text{MoTe}_2$ and graphene-based heterostructures provided evidence of fractional quantum anomalous Hall (FQAH) states, which spontaneously break time-reversal symmetry and persist even without an external magnetic field. Understanding the unique properties of these states requires the characterization of their low-energy excitations. To that end, we construct a parton theory for the energy and momentum-resolved single-particle spectral function of FQAH states. We explicitly consider several experimentally observed filling fractions as well as a composite Fermi liquid in the half-filled Chern band. The parton description qualitatively captures our numerical exact diagonalization results. Additionally, we discuss how the finite bandwidth of the Chern band and the non-ideal quantum geometry affect the fractionalized excitations. Our work demonstrates that the energy and momentum-resolved electronic single-particle spectral function provides a valuable tool to characterize fractionalized excitations of FQAH states in moiré lattices.
format Preprint
id arxiv_https___arxiv_org_abs_2410_07319
institution arXiv
publishDate 2024
record_format arxiv
spellingShingle Single-particle spectral function of fractional quantum anomalous Hall states
Pichler, Fabian
Kadow, Wilhelm
Kuhlenkamp, Clemens
Knap, Michael
Mesoscale and Nanoscale Physics
Strongly Correlated Electrons
Fractional quantum Hall states are the most prominent example of states with topological order, hosting excitations with fractionalized charge. Recent experiments in twisted $\text{MoTe}_2$ and graphene-based heterostructures provided evidence of fractional quantum anomalous Hall (FQAH) states, which spontaneously break time-reversal symmetry and persist even without an external magnetic field. Understanding the unique properties of these states requires the characterization of their low-energy excitations. To that end, we construct a parton theory for the energy and momentum-resolved single-particle spectral function of FQAH states. We explicitly consider several experimentally observed filling fractions as well as a composite Fermi liquid in the half-filled Chern band. The parton description qualitatively captures our numerical exact diagonalization results. Additionally, we discuss how the finite bandwidth of the Chern band and the non-ideal quantum geometry affect the fractionalized excitations. Our work demonstrates that the energy and momentum-resolved electronic single-particle spectral function provides a valuable tool to characterize fractionalized excitations of FQAH states in moiré lattices.
title Single-particle spectral function of fractional quantum anomalous Hall states
topic Mesoscale and Nanoscale Physics
Strongly Correlated Electrons
url https://arxiv.org/abs/2410.07319