Probing Exciton Dispersions of Freestanding Monolayer WSe<sub>2</sub> by Momentum-Resolved Electron Energy-Loss Spectroscopy

Author(s)
Jinhua Hong, Ryosuke Senga, Thomas Pichler, Kazu Suenaga
Abstract

Momentum resolved electron energy-loss spectroscopy was used to measure the dispersions of excitons in a free-standing monolayer of WSe2. Besides the parabolically dispersed valley excitons, a sub-gap dispersive exciton was observed at specific q values for the first time. The simultaneous STEM-ADF imaging of the local probed areas suggests that this sub-gap exciton is attributed to the prolific Se vacancies.

Organisation(s)
Electronic Properties of Materials
External organisation(s)
National Institute of Advanced Industrial Science and Technology (AIST)
Journal
Physical Review Letters
Volume
124
No. of pages
5
ISSN
0031-9007
DOI
https://doi.org/10.1103/PhysRevLett.124.087401
Publication date
09-2019
Peer reviewed
Yes
Austrian Fields of Science 2012
Condensed matter
Keywords
Portal url
https://ucris.univie.ac.at/portal/en/publications/probing-exciton-dispersions-of-freestanding-monolayer-wse2-by-momentumresolved-electron-energyloss-spectroscopy(cebbc22d-a0a4-4de0-91f8-82ecc3326f3e).html