Dark-bright exciton coupling in asymmetric quantum dots
نویسندگان
چکیده
منابع مشابه
Band-edge exciton in quantum dots of semiconductors with a degenerate valence band: Dark and bright exciton states.
We present a theoretical analysis of the band-edge exciton structure in nanometer-size crystallites of direct semiconductors with a cubic lattice structure or a hexagonal lattice structure which can be described within the framework of a quasicubic model. The lowest energy exciton, eightfold degenerate in spherically symmetric dots, is split into five levels by the crystal shape asymmetry, the ...
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Coupling of acoustic phonons to excitons in single wurtzite-type GaN/AlN quantum dots is investigated in detail by cathodoluminescence experiments and compared to theory. Numerical simulations of the coupling in the framework of the independent Boson model with realistic wave functions based on 8-band k · p theory show good agreement with observed emission line shapes. We analyze the influence ...
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ژورنال
عنوان ژورنال: Physical Review B
سال: 2018
ISSN: 2469-9950,2469-9969
DOI: 10.1103/physrevb.98.155303