Effects of GaAs-spacer strain on vertical ordering of stacked InAs quantum dots in a GaAs matrix |
| |
Authors: | S Rouvimov Z Liliental-Weber W Swider J Washburn E R Weber A Sasaki A Wakahara Y Furkawa T Abe S Noda |
| |
Affiliation: | (1) Present address: A.F. Ioffe Physical-Technical Institute, 194021 St.-Petersburg, Russia;(2) Lawrence Berkeley National Laboratory, 94720 Berkeley, CA;(3) Osaka Electro-Communication University, 570 Neyagawashi, Japan;(4) Kyoto University, 60601 Kyoto, Japan |
| |
Abstract: | Vertical ordering in stacked layers of InAs/GaAs quantum dots is currently the focus of scientific research because of its
potential for optoelectronics applications. Transmission electron microscopy was applied to study InAs/GaAs stacked layers
grown by molecular-beam-epitaxy with various thicknesses of GaAs spacer. Thickness dependencies of quantum dot size and their
ordering were observed experimentally and, then, compared with the results of strain calculations based on the finite element
method. The vertical ordering did occur when the thickness of the GaAs spacer was comparable with the dot height. The ordering
was found to be associated with relatively large InAs dots on the first layer. Quantum dots tend to become larger in size
and more regular in plane with increasing numbers of stacks. Our results suggest that the vertical ordering is not only affected
by strain from the InAs dots on the lower layer, but by total strain configuration in the multi-stacked structure. |
| |
Keywords: | InAs/GaAs quantum dots strain vertical ordering |
本文献已被 SpringerLink 等数据库收录! |
|