Influence of the domain size on the band gap of ordered (GaIn)P

Citation
T. Sass et al., Influence of the domain size on the band gap of ordered (GaIn)P, J APPL PHYS, 85(7), 1999, pp. 3561-3564
Citations number
24
Language
INGLESE
art.tipo
Article
Categorie Soggetti
Apllied Physucs/Condensed Matter/Materiales Science
Journal title
JOURNAL OF APPLIED PHYSICS
ISSN journal
0021-8979 → ACNP
Volume
85
Issue
7
Year of publication
1999
Pages
3561 - 3564
Database
ISI
SICI code
0021-8979(19990401)85:7<3561:IOTDSO>2.0.ZU;2-6
Abstract
The domain size and the band-gap energy of ordered epitaxial (GaIn)P layers have been determined by means of transmission electron microscopy and phot oluminescence measurements, respectively. With decreasing domain size the s ymmetry of the ordered layers is reduced from the trigonal space group R3m (CuPtB type) to the monoclinic Pm space group. Pseudopotential band-structu re calculations reveal an increase of the band-gap energy of ordered (GaIn) P with diminishing domain size. This would affect the determination of the degree of order by methods, which rely on the band-gap energy of perfectly ordered (GaIn)P. By correlating the theoretical with the experimental band- gap energies we demonstrate that the order parameter eta of layers with sma ll domains is higher if the dependence of the band-gap energy on the domain size is considered. Hence, for the determination of the degree of order no t only the band-gap energy, but also the domain size have to be taken into account. (C) 1999 American Institute of Physics. [S0021-8979(99)06207-6].