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Title: Coulomb engineering of the bandgap and excitons in two-dimensional materials

Abstract

Here, the ability to control the size of the electronic bandgap is an integral part of solid-state technology. Atomically thin two-dimensional crystals offer a new approach for tuning the energies of the electronic states based on the unusual strength of the Coulomb interaction in these materials and its environmental sensitivity. Here, we show that by engineering the surrounding dielectric environment, one can tune the electronic bandgap and the exciton binding energy in monolayers of WS 2 and WSe 2 by hundreds of meV. We exploit this behaviour to present an in-plane dielectric heterostructure with a spatially dependent bandgap, as an initial step towards the creation of diverse lateral junctions with nanoscale resolution.

Authors:
 [1];  [2];  [3];  [3];  [4];  [4];  [5];  [6];  [6];  [6]; ORCiD logo [3];  [3];  [3];  [1];  [3];  [7]
  1. Columbia Univ., New York, NY (United States); Stanford Univ., Stanford, CA (United States); SLAC National Accelerator Lab., Menlo Park, CA (United States)
  2. Columbia Univ., New York, NY (United States); Univ. Federal do Ceara, Fortaleza (Brazil)
  3. Columbia Univ., New York, NY (United States)
  4. Columbia Univ., New York, NY (United States); Stanford Univ., Stanford, CA (United States)
  5. Univ. of Chicago, Chicago, IL (United States)
  6. Univ. of Regensburg, Regensburg (Germany)
  7. Columbia Univ., New York, NY (United States); Univ. of Regensburg, Regensburg (Germany)
Publication Date:
Research Org.:
SLAC National Accelerator Lab. (SLAC), Menlo Park, CA (United States)
Sponsoring Org.:
USDOE
OSTI Identifier:
1360901
Grant/Contract Number:
AC02-76SF00515
Resource Type:
Journal Article: Accepted Manuscript
Journal Name:
Nature Communications
Additional Journal Information:
Journal Volume: 8; Journal ID: ISSN 2041-1723
Publisher:
Nature Publishing Group
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; electronic properties and materials; two-dimensional materials

Citation Formats

Raja, Archana, Chaves, Andrey, Yu, Jaeeun, Arefe, Ghidewon, Hill, Heather M., Rigosi, Albert F., Berkelbach, Timothy C., Nagler, Philipp, Schuller, Christian, Korn, Tobias, Nuckolls, Colin, Hone, James, Brus, Louis E., Heinz, Tony F., Reichman, David R., and Chernikov, Alexey. Coulomb engineering of the bandgap and excitons in two-dimensional materials. United States: N. p., 2017. Web. doi:10.1038/ncomms15251.
Raja, Archana, Chaves, Andrey, Yu, Jaeeun, Arefe, Ghidewon, Hill, Heather M., Rigosi, Albert F., Berkelbach, Timothy C., Nagler, Philipp, Schuller, Christian, Korn, Tobias, Nuckolls, Colin, Hone, James, Brus, Louis E., Heinz, Tony F., Reichman, David R., & Chernikov, Alexey. Coulomb engineering of the bandgap and excitons in two-dimensional materials. United States. doi:10.1038/ncomms15251.
Raja, Archana, Chaves, Andrey, Yu, Jaeeun, Arefe, Ghidewon, Hill, Heather M., Rigosi, Albert F., Berkelbach, Timothy C., Nagler, Philipp, Schuller, Christian, Korn, Tobias, Nuckolls, Colin, Hone, James, Brus, Louis E., Heinz, Tony F., Reichman, David R., and Chernikov, Alexey. Thu . "Coulomb engineering of the bandgap and excitons in two-dimensional materials". United States. doi:10.1038/ncomms15251. https://www.osti.gov/servlets/purl/1360901.
@article{osti_1360901,
title = {Coulomb engineering of the bandgap and excitons in two-dimensional materials},
author = {Raja, Archana and Chaves, Andrey and Yu, Jaeeun and Arefe, Ghidewon and Hill, Heather M. and Rigosi, Albert F. and Berkelbach, Timothy C. and Nagler, Philipp and Schuller, Christian and Korn, Tobias and Nuckolls, Colin and Hone, James and Brus, Louis E. and Heinz, Tony F. and Reichman, David R. and Chernikov, Alexey},
abstractNote = {Here, the ability to control the size of the electronic bandgap is an integral part of solid-state technology. Atomically thin two-dimensional crystals offer a new approach for tuning the energies of the electronic states based on the unusual strength of the Coulomb interaction in these materials and its environmental sensitivity. Here, we show that by engineering the surrounding dielectric environment, one can tune the electronic bandgap and the exciton binding energy in monolayers of WS2 and WSe2 by hundreds of meV. We exploit this behaviour to present an in-plane dielectric heterostructure with a spatially dependent bandgap, as an initial step towards the creation of diverse lateral junctions with nanoscale resolution.},
doi = {10.1038/ncomms15251},
journal = {Nature Communications},
number = ,
volume = 8,
place = {United States},
year = {Thu May 04 00:00:00 EDT 2017},
month = {Thu May 04 00:00:00 EDT 2017}
}

Journal Article:
Free Publicly Available Full Text
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Cited by: 23works
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