Effects of Point Defects on the Optical Spectra of Monolayer Transition Metal Dichalcogenides

ORAL

Abstract

Point defects are known to play an important role in the optical properties of quasi-two-dimensional materials. For instance, the photoluminescence spectra of transition metal dichalcogenides (TMDs) show broad, low energy features that are attributed to defects, and researchers have proposed exploiting defects in TMDs as catalytic centers and single-photon emitters. We use the GW and GW-BSE approach to study the quasiparticle energy levels and optical spectra associated with point defects in monolayer TMDs. We find that defect-state excitons hybridize very strongly with normal excitons in the pristine monolayer, allowing a defect to act as an exciton trap or as a pathway for exciton dephasing.

*This work was supported by C2SEPEM, which is funded by the U.S. DoE, 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.

–

Presenters

  • Diana Qiu

    • Physics, University of California, Berkeley
    • Physics, Univ of California - Berkeley
    • Lawrence Berkeley National Lab and University of California - Berkeley

Authors

  • Diana Qiu

    • Physics, University of California, Berkeley
    • Physics, Univ of California - Berkeley
    • Lawrence Berkeley National Lab and University of California - Berkeley

  • Sivan Refaely-Abramson

    • Department of Physics, UC Berkeley; Molecular Foundry, LBNL
    • Dept. of Materials and Interfaces, Weizmann Institute of Science
    • Lawrence Berkeley National Laboratory
    • Lawrence Berkeley National Lab and University of California - Berkeley

  • Jeffrey Neaton

    • Molecular Foundry, Lawrence Berkeley National Laboratory; Department of Physics, University of California, Berkeley; Kavli Energy Nanosciences Institute at Berkeley
    • Physics, University of California, Berkeley; Lawrence Berkeley National Laboratory
    • Department of Physics, University of California
    • Univ of California - Berkeley
    • Lawrence Berkeley Natl Lab
    • Materials Science Division, Lawrence Berkeley National Laboratory
    • Molecular Foundry, Lawrence Berkeley National Lab
    • Physics, University of California, Berkeley
    • Department of Physics UCB; Molecular Foundry LBNL; Kavli ENSI
    • Lawrence Berkeley National Laboratory
    • Department of Physics, Univ of California - Berkeley
    • Lawrence Berkeley National Lab and University of California - Berkeley

  • Steven Louie

    • Physics, University of California, Berkeley
    • University of California, Berkeley
    • Physics, Univ of California - Berkeley
    • Univ of California - Berkeley
    • Physics, UC Berkeley
    • Physics Department, UC Berkeley and Lawrence Berkeley National Lab
    • Department of Physics, University of California at Berkeley and Materials Sciences Division, Lawrence Berkeley National Laboratory
    • Department of Physics, University of California, Berkeley
    • Physics Department, University of California Berkeley and Lawrence Berkeley National Lab
    • Department of physics, University of California - Berkeley
    • Lawrence Berkeley National Lab and University of California - Berkeley
    • Materials Sciences Division, Lawrence Berkeley National Laboratory & Department of Physics, University of California at Berkeley
    • UC Berkeley and Lawrence Berkeley National Lab
    • Physics, University of California - Berkeley