Growth control, structure and ferromagnetic properties of digital Mn/GaAs heterostructures

• Published in: Journal of crystal growth 2005-05, Vol.278 (1), p.655-660
• Main Authors: Guo, X.X., Herrmann, C., Kong, X., Kolovos-Vellianitis, D., Däweritz, L., Ploog, K.H.
• Format: Article
• Language: English
• Subjects: A1. Reflection high-energy electron diffraction; A3. Molecular beam epitaxy; B2. (Ga,Mn)As digital heterostructures; B2. Magnetic materials; Condensed matter: electronic structure, electrical, magnetic, and optical properties; Condensed matter: structure, mechanical and thermal properties; Defects and impurities in crystals; microstructure; Exact sciences and technology; Interfacial magnetic properties (multilayers, magnetic quantum wells, superlattices, magnetic heterostructures); Magnetic properties and materials; Magnetic properties of surface, thin films and multilayers; Physics; Stacking faults and other planar or extended defects; Structure of solids and liquids; crystallography
• ISSN: 0022-0248; 1873-5002
• DOI: 10.1016/j.jcrysgro.2004.12.122

The growth of digital Mn/GaAs heterostructures with high Mn sheet densities has been studied at widely varied As 4 pressures by in situ RHEED monitoring and microstructure characterization using TEM. In particular for heterostructures with a large number of periods, the evolution of the specular RHEED beam intensity can be advantageously used for growth control. Analysis of the influence of the Mn density and As 4 pressure on the ferromagnetic properties of the heterostructures suggests a correlation with intrinsic defects in the Mn sheets as well as in the GaAs spacers. Stacking faults are found to be the dominant growth defect.