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

fYear

2002

fDate

15-20 Sept. 2002

Firstpage

413

Lastpage

414

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;

fLanguage

English

Publisher

ieee

Conference_Titel

Molecular Beam Epitaxy, 2002 International Conference on

Conference_Location

San Francisco, CA, USA

Print_ISBN

0-7803-7581-5

Type

conf

DOI

10.1109/MBE.2002.1037934

Filename

1037934