%0 Journal Article
%T Ge Quantum Dots Encapsulated by AlAs Grown by Molecular Beam Epitaxy on GaAs Without Extended Defects
%A Meng Qi
%A Chad A. Stephenson
%A Vladimir Protasenko
%A William A. O'Brien
%A Alexander Mintairov
%A Huili Grace Xing
%A Mark A. Wistey
%J Physics
%D 2013
%I arXiv
%R 10.1063/1.4866278
%X We demonstrate nearly-spherical, strain-free, self-assembled Ge quantum dots (QDs) fully encapsulated by AlAs, grown on (100) GaAs by molecular beam epitaxy (MBE). The QDs were formed without a wetting layer using a high temperature, in-situ anneal. Subsequent AlAs overgrowth was free from threading dislocations and anti-phase domains. The straddling band alignment for Ge in AlAs promises strong and tunable confinement for both electrons and holes. The reflection high-energy electron diffraction (RHEED) pattern changed from 2x3 to 2x5 with anneal, which can be explained by surface reconstructions based on the electron-counting model.
%U http://arxiv.org/abs/1311.1448v1