GaMnAs on InGaAs templates: Influence of strain on the electronic and magnetic properties

✍ Scribed by J. Daeubler; S. Schwaiger; M. Glunk; M. Tabor; W. Schoch; R. Sauer; W. Limmer

• Publisher: Elsevier Science
• Year: 2008
• Tongue: English
• Weight: 173 KB
• Volume: 40
• Category: Article
• ISSN: 1386-9477
• DOI: 10.1016/j.physe.2007.08.049

✦ Synopsis

We present a systematic study on the influence of strain on the electronic and magnetic properties of GaMnAs. A series of GaMnAs layers was grown on relaxed InGaAs/GaAs templates, enabling us to vary the strain in the GaMnAs layers continuously from tensile to compressive, including unstrained samples. The as-grown GaMnAs layers showed no apparent dependence of hole density and Curie temperature on strain, whereas a systematic linear variation of the uniaxial out-of-plane magnetic anisotropy was found. From compressive to tensile strain, the out-of-plane direction gradually undergoes a transition from a magnetic hard axis to a magnetic easy axis. Low-temperature post-growth annealing leads to an increase in hole density and a decrease of the relaxed lattice parameter of GaMnAs, resulting in a pronounced enhancement of the uniaxial out-of-plane anisotropy.