TY - JOUR
T1 - Defect-Induced Modification of Low-Lying Excitons and Valley Selectivity in Monolayer Transition Metal Dichalcogenides
AU - Refaely-Abramson, Sivan
AU - Qiu, Diana Y.
AU - Louie, Steven G.
AU - Neaton, Jeffrey B.
N1 - We thank Felipe H. da Jornada, Jack Deslippe, and Mauro Del Ben for valuable discussions. This work was supported by the Center for Computational Study of Excited State Phenomena in Energy Materials, which is funded by the U.S. Department of Energy, Office of Science, Basic Energy Sciences, Materials Sciences and Engineering Division under Contract No. DE-AC02-05CH11231, as part of the Computational Materials Sciences Program. Work performed at the Molecular Foundry was also supported by the Office of Science, Office of Basic Energy Sciences, of the U.S. Department of Energy under the same contract number. S. R. A. acknowledges Rothschild and Fulbright fellowships. This research used resources of the National Energy Research Scientific Computing Center (NERSC), a DOE Office of Science User Facility supported by the Office of Science of the U.S. Department of Energy under Contract No. DE-AC02-05CH11231. S. R.-A. and D. Y. Q. contributed equally to this work.
PY - 2018/10/19
Y1 - 2018/10/19
N2 - We study the effect of point-defect chalcogen vacancies on the optical properties of monolayer transition metal dichalcogenides using ab initio GW and Bethe-Salpeter equation calculations. We find that chalcogen vacancies introduce unoccupied in-gap states and occupied resonant defect states within the quasiparticle continuum of the valence band. These defect states give rise to a number of strongly bound defect excitons and hybridize with excitons of the pristine system, reducing the valley-selective circular dichroism. Our results suggest a pathway to tune spin-valley polarization and other optical properties through defect engineering.
AB - We study the effect of point-defect chalcogen vacancies on the optical properties of monolayer transition metal dichalcogenides using ab initio GW and Bethe-Salpeter equation calculations. We find that chalcogen vacancies introduce unoccupied in-gap states and occupied resonant defect states within the quasiparticle continuum of the valence band. These defect states give rise to a number of strongly bound defect excitons and hybridize with excitons of the pristine system, reducing the valley-selective circular dichroism. Our results suggest a pathway to tune spin-valley polarization and other optical properties through defect engineering.
UR - http://www.scopus.com/inward/record.url?scp=85055171903&partnerID=8YFLogxK
U2 - 10.1103/PhysRevLett.121.167402
DO - 10.1103/PhysRevLett.121.167402
M3 - مقالة
SN - 0031-9007
VL - 121
JO - Physical review letters
JF - Physical review letters
IS - 16
M1 - 167402
ER -