Publication
Title
Configuration-interaction excitonic absorption in small Si/Ge and Ge/Si core/shell nanocrystals
Author
Abstract
The excitonic properties of Si(core)/Ge(shell) and Ge(core)/Si(shell) nanocrystals (NC's) with diameters of similar to 1.9 nm are investigated using a combination density functional ab initio method to obtain the single particle wave functions and a configuration interaction method to compute the exciton fine structure and absorption coefficient. These core/shell structures exhibit type II confinement, which is more pronounced for the Si/Ge NC as a consequence of strain. The absorption coefficients of these NC's exhibit a single dominant peak, which has a much larger oscillator strength than the multipeaks found for pure Si and Ge NC's. The exciton lifetime in Si, Ge, and Ge/Si shows a small i:emperature dependence in the range 10-300 K, whereas in Si/Ge, the exciton lifetime decreases more than an order of magnitude in the same temperature range.
Language
English
Source (journal)
The journal of physical chemistry : C : nanomaterials and interfaces. - Washington, D.C., 2007, currens
Publication
Washington, D.C. : 2012
ISSN
1932-7447 [print]
1932-7455 [online]
Volume/pages
116:7(2012), p. 4399-4407
ISI
000301156500007
Full text (Publisher's DOI)
UAntwerpen
Faculty/Department
Research group
Publication type
Subject
Affiliation
Publications with a UAntwerp address
External links
Web of Science
Record
Identification
Creation 22.01.2014
Last edited 10.09.2017
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