Artículos de revistas
Structural and optical properties of InP quantum dots grown on GaAs(001)
Registro en:
Journal Of Applied Physics. Amer Inst Physics, v. 101, n. 7, 2007.
0021-8979
WOS:000245691000028
10.1063/1.2718869
Autor
de Godoy, MPF
Nakaema, MKK
Iikawa, F
Brasil, MJSP
Lopes, JMJ
Bortoleto, JRR
Cotta, MA
Magalhaes-Paniago, R
Morschbacher, MJ
Fichtner, PFP
Institución
Resumen
We investigated structural and optical properties of type-II InP/GaAs quantum dots using reflection high energy electron diffraction, transmission electron microscopy, atomic force microscopy, grazing incidence x-ray diffraction, and photoluminescence techniques. The InP dots present an efficient optical emission even when they are uncapped, which is attributed to the low surface recombination velocity in InP. We compare the difference in the optical properties between surface free dots, which are not covered by any material, with dots covered by a GaAs capping layer. We observed a bimodal dispersion of the dot size distribution, giving rise to two distinct emission bands. The results also revealed that the strain accumulated in the InP islands is slightly relieved for samples with large InP amounts. An unexpected result is the relatively large blue shift of the emission band from uncapped samples as compared to capped dots. (c) 2007 American Institute of Physics. 101 7