skip to main content

DOE PAGESDOE PAGES

This content will become publicly available on September 15, 2019

Title: Strain tuning of excitons in monolayer WSe 2

Here, we investigate excitonic absorption and emission in monolayer (1L) WSe 2 under tensile strain. We observe a redshift of 100 meV in the A exciton energy and a decrease of 25 meV in its estimated binding energy under 2.1% strain. Surprisingly, the linewidth of the A exciton decreases by almost a factor of two under strain, from 42 to 24 meV at room temperature. We explain this effect as the result of suppression of phonon-mediated exciton scattering channels. We show that such a suppression results from the relative shift under strain of a secondary valley in the conduction band that is nearly degenerate with the K valley where the A exciton is formed.
Authors:
 [1] ;  [1] ;  [1]
  1. Stanford Univ., Stanford, CA (United States); SLAC National Accelerator Lab., Menlo Park, CA (United States)
Publication Date:
Grant/Contract Number:
AC02-76SF00515
Type:
Accepted Manuscript
Journal Name:
Physical Review B
Additional Journal Information:
Journal Volume: 98; Journal Issue: 11; Journal ID: ISSN 2469-9950
Publisher:
American Physical Society (APS)
Research Org:
Stanford Univ., CA (United States)
Sponsoring Org:
USDOE Office of Science (SC), Basic Energy Sciences (BES) (SC-22)
Country of Publication:
United States
Language:
English
Subject:
77 NANOSCIENCE AND NANOTECHNOLOGY; excitons; phonons; 2-dimensional systems; transition-metal dichalcogenides; monolayer films; optical absorption and photoluminescence spectroscopy; strain engineering
OSTI Identifier:
1474105
Alternate Identifier(s):
OSTI ID: 1474195

Aslan, Ozgur Burak, Deng, Minda, and Heinz, Tony F. Strain tuning of excitons in monolayer WSe2. United States: N. p., Web. doi:10.1103/PhysRevB.98.115308.
Aslan, Ozgur Burak, Deng, Minda, & Heinz, Tony F. Strain tuning of excitons in monolayer WSe2. United States. doi:10.1103/PhysRevB.98.115308.
Aslan, Ozgur Burak, Deng, Minda, and Heinz, Tony F. 2018. "Strain tuning of excitons in monolayer WSe2". United States. doi:10.1103/PhysRevB.98.115308.
@article{osti_1474105,
title = {Strain tuning of excitons in monolayer WSe2},
author = {Aslan, Ozgur Burak and Deng, Minda and Heinz, Tony F.},
abstractNote = {Here, we investigate excitonic absorption and emission in monolayer (1L) WSe2 under tensile strain. We observe a redshift of 100 meV in the A exciton energy and a decrease of 25 meV in its estimated binding energy under 2.1% strain. Surprisingly, the linewidth of the A exciton decreases by almost a factor of two under strain, from 42 to 24 meV at room temperature. We explain this effect as the result of suppression of phonon-mediated exciton scattering channels. We show that such a suppression results from the relative shift under strain of a secondary valley in the conduction band that is nearly degenerate with the K valley where the A exciton is formed.},
doi = {10.1103/PhysRevB.98.115308},
journal = {Physical Review B},
number = 11,
volume = 98,
place = {United States},
year = {2018},
month = {9}
}

Works referenced in this record:

Bandgap Engineering of Strained Monolayer and Bilayer MoS2
journal, July 2013
  • Conley, Hiram J.; Wang, Bin; Ziegler, Jed I.
  • Nano Letters, Vol. 13, Issue 8, p. 3626-3630
  • DOI: 10.1021/nl4014748

Band structure, deformation potentials, and carrier mobility in strained Si, Ge, and SiGe alloys
journal, August 1996
  • Fischetti, M. V.; Laux, S. E.
  • Journal of Applied Physics, Vol. 80, Issue 4, p. 2234-2252
  • DOI: 10.1063/1.363052