Title :
Structural and magnetic order in MnAs films grown by molecular beam epitaxy on GaAs for spin injection
Author :
Däweritz, L. ; Kästner, M. ; Hesjedal, T. ; Plake, T. ; Jenichen, B. ; Ploog, K.H.
Author_Institution :
Paul-Drude-Inst. fur Festkorperelektronik, Berlin, Germany
Abstract :
Epitaxial MnAs films on GaAs are of interest as ferromagnetic layers suitable for spin injection into semiconductors. Recent studies revealed that the phase transition near room temperature from the paramagnetic orthorhombic /spl beta/ phase above 40/spl deg/C to the ferromagnetic hexagonal /spl alpha/ phase below 40/spl deg/C is of crucial importance for the structural and magnetic properties of the films. In this paper we report about ordered structures of the coexisting phases as a result of epitaxial strain and demonstrate the strong coupling between the magnetic order and the two-phase system.
Keywords :
III-V semiconductors; crystal structure; ferromagnetic materials; ferromagnetic-paramagnetic transitions; gallium arsenide; magnetic epitaxial layers; magnetic semiconductors; magnetic structure; manganese compounds; molecular beam epitaxial growth; semiconductor epitaxial layers; semiconductor growth; solid-state phase transformations; 20 C; 250 C; 40 C; GaAs; MnAs films; MnAs-GaAs; epitaxial MnAs films; epitaxial strain; ferromagnetic hexagonal /spl alpha/ phase; ferromagnetic layers; magnetic order; molecular beam epitaxy; ordered structures; paramagnetic orthorhombic /spl beta/ phase; phase transition; room temperature; spin injection; structural order; two-phase system; Gallium arsenide; Magnetic field induced strain; Magnetic films; Magnetic properties; Magnetic semiconductors; Molecular beam epitaxial growth; Paramagnetic materials; Semiconductor films; Spin polarized transport; Temperature;
Conference_Titel :
Molecular Beam Epitaxy, 2002 International Conference on
Conference_Location :
San Francisco, CA, USA
Print_ISBN :
0-7803-7581-5
DOI :
10.1109/MBE.2002.1037934
