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Title: Topological Exciton Bands in Moire Heterojunctions.

Abstract

Moire patterns are common in Van der Waals heterostructures and can be used to apply periodic potentials to elementary excitations. Here, we show that the optical absorption spectrum of transition metal dichalcogenide bilayers is profoundly altered by long period moire patterns that introduce twist-angle dependent satellite excitonic peaks. Topological exciton bands with non-zero Chern numbers that support chiral excitonic edge states can be engineered by combining three ingredients: i) the valley Berry phase induced by electron-hole exchange interactions, ii) the moire potential, and iii) the valley Zeeman field.

Authors:
 [1];  [2];  [2]
  1. Univ. of Texas, Austin, TX (United States). Dept. of Physics; Argonne National Lab. (ANL), Argonne, IL (United States). Materials Science Division
  2. Univ. of Texas, Austin, TX (United States). Dept. of Physics
Publication Date:
Research Org.:
Argonne National Lab. (ANL), Argonne, IL (United States)
Sponsoring Org.:
USDOE Office of Science (SC), Basic Energy Sciences (BES) (SC-22); Welch foundation
OSTI Identifier:
1352892
Alternate Identifier(s):
OSTI ID: 1349974
Grant/Contract Number:
AC02-06CH11357; SC0012670
Resource Type:
Journal Article: Accepted Manuscript
Journal Name:
Physical Review Letters
Additional Journal Information:
Journal Volume: 118; Journal Issue: 14; Journal ID: ISSN 0031-9007
Publisher:
American Physical Society (APS)
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE

Citation Formats

Wu, Fengcheng, Lovorn, Timothy, and MacDonald, A. H.. Topological Exciton Bands in Moire Heterojunctions.. United States: N. p., 2017. Web. doi:10.1103/PhysRevLett.118.147401.
Wu, Fengcheng, Lovorn, Timothy, & MacDonald, A. H.. Topological Exciton Bands in Moire Heterojunctions.. United States. doi:10.1103/PhysRevLett.118.147401.
Wu, Fengcheng, Lovorn, Timothy, and MacDonald, A. H.. Wed . "Topological Exciton Bands in Moire Heterojunctions.". United States. doi:10.1103/PhysRevLett.118.147401. https://www.osti.gov/servlets/purl/1352892.
@article{osti_1352892,
title = {Topological Exciton Bands in Moire Heterojunctions.},
author = {Wu, Fengcheng and Lovorn, Timothy and MacDonald, A. H.},
abstractNote = {Moire patterns are common in Van der Waals heterostructures and can be used to apply periodic potentials to elementary excitations. Here, we show that the optical absorption spectrum of transition metal dichalcogenide bilayers is profoundly altered by long period moire patterns that introduce twist-angle dependent satellite excitonic peaks. Topological exciton bands with non-zero Chern numbers that support chiral excitonic edge states can be engineered by combining three ingredients: i) the valley Berry phase induced by electron-hole exchange interactions, ii) the moire potential, and iii) the valley Zeeman field.},
doi = {10.1103/PhysRevLett.118.147401},
journal = {Physical Review Letters},
number = 14,
volume = 118,
place = {United States},
year = {Wed Apr 05 00:00:00 EDT 2017},
month = {Wed Apr 05 00:00:00 EDT 2017}
}

Journal Article:
Free Publicly Available Full Text
Publisher's Version of Record

Citation Metrics:
Cited by: 9works
Citation information provided by
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