1. Orbital Symmetry and the Optical Response of Single-Layer MX Monochalcogenides.
- Author
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Antonius, Gabriel, Qiu, Diana Y., and Louie, Steven G.
- Subjects
- *
EXCITON theory , *LIGHT absorption , *POLARIZATION (Electricity) , *LIGHT absorbance , *ABSORPTION spectra , *QUANTUM theory - Abstract
We show that the absorption spectra of single-layer GaSe and GaTe in the hexagonal phase feature exciton peaks with distinct polarization selectivity. We investigate these distinct features from first-principles calculations using the GW-BSE formalism. We show that, because of the symmetry of the bands under in-plane mirror symmetry, the bound exciton states selectively couple to either in-plane or out-of-plane polarization of the light. In particular, for a p-polarized light absorption experiment, the absorption peaks of the hydrogenic s-like excitons emerge at large angle of incidence, while the overall absorbance reduces over the rest of the spectrum. [ABSTRACT FROM AUTHOR]
- Published
- 2018
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