TITLE

Spatially direct and indirect transitions observed for Si/Ge quantum dots

AUTHOR(S)
Larsson, M.; Elfving, A.; Holtz, P. O.; Hansson, G. V.; Ni, W.-X.
PUB. DATE
June 2003
SOURCE
Applied Physics Letters;6/30/2003, Vol. 82 Issue 26, p4785
SOURCE TYPE
Academic Journal
DOC. TYPE
Article
ABSTRACT
The optical properties of Ge quantum dots embedded in Si were investigated by means of photoluminescence, with temperature and excitation power density as variable parameters. Two different types of recombination processes related to the Ge quantum dots were observed. A transfer from the spatially indirect to the spatially direct recombination in the type-II band lineup was observed with increasing temperature. A blueshift of the spatially indirect Ge quantum-dot-emission energy with increasing excitation power is ascribed to band bending at the type-II Si/Ge interface for high carrier densities. Comparative studies were performed on uncapped Ge dot structures.
ACCESSION #
10106472

 

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