Point contact Andreev spectroscopy of epitaxial Co{sub 2}FeSi Heusler alloys on GaAs (001)

Journal Article · Thu Sep 15 00:00:00 EDT 2011 · Journal of Applied Physics

DOI:https://doi.org/10.1063/1.3632063· OSTI ID:22038712

Lehmann, Hauke; Merkt, Ulrich; Meier, Guido ^[1]; Scholtyssek, Jan M ^[1]; Herrmann, Claudia; Herfort, Jens ^[2]

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1. Institut fuer Angewandte Physik und Zentrum fuer Mikrostrukturforschung, Universitaet Hamburg, Jungiusstrasse 11, 20355 Hamburg (Germany)
2. Paul-Drude-Institut fuer Festkoerperelektronik, Hausvogteiplatz 5-7, 10117 Berlin (Germany)

The predicted half-metallicity of Co{sub 2}FeSi in combination with its high Curie temperature of above 980 K makes this Heusler alloy interesting for spinelectronics. Thin Co{sub 2}FeSi films are grown by molecular-beam epitaxy on GaAs (001) with a close lattice match. We present a study of point-contact measurements on different films, varying in thickness between 18 nm and 48 nm and in substrate temperature during deposition between 100 deg. C and 300 deg. C. Transport spin polarizations at the Fermi level are determined from differential conductance curves obtained by point-contact Andreev-reflection spectroscopy. A maximum transport spin polarization of about 60% is measured for a 18 nm thin Co{sub 2}FeSi film grown at 200 deg. C.

• OSTI ID: 22038712
• Journal Information: Journal of Applied Physics, Vol. 110, Issue 6; Other Information: (c) 2011 American Institute of Physics; Country of input: International Atomic Energy Agency (IAEA); ISSN 0021-8979
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
COBALT ALLOYS
CURIE POINT
DEPOSITION
ELECTRONS
FERMI LEVEL
GALLIUM ARSENIDES
HEUSLER ALLOYS
IRON ALLOYS
LAYERS
MOLECULAR BEAM EPITAXY
POLARIZATION
REFLECTION
REFLECTIVITY
SILICON ALLOYS
SPECTROSCOPY
SPIN
SPIN ORIENTATION
SUBSTRATES