Tunneling Anisotropic Magnetoresistance effect in p+-(Ga,Mn)As/n+-GaAs Esaki diode structure.
|Andreas Einwanger 1, Mariusz Ciorga 1, Janusz Sadowski 1,2,3, Werner Wegscheider 1, Dieter Weiss 1|
1. Institut für Experimentelle und Angewandte Physik Universität Regensburg (Uni. Regensb), Universitätsstraße 31, Regensburg 93040, Germany
We have fabricated devices to investigate electrical spin injection from a ferromagnetic (Ga,Mn)As layer into a non-magnetic GaAs layer in the lateral transport geometry. The Esaki diode structure p+-(Ga,Mn)As/n+-GaAs is used to circumvent the problem of fast spin relaxation of holes injected from a p-type ferromagnet into GaAs. Under a reverse bias applied to such a structure spin-polarized electrons, with longer spin relaxation times than holes, tunnel from (Ga,Mn)As valence band through the depletion layer into GaAs conduction band . Here we report on magnetotransport investigations of the Esaki diode in both in-plane and perpendicular external magnetic field. The sample was rotated in the in-plane field to investigate the dependence of the resulting magnetoresistance on the angle between applied in-plane field and directions of crystallographic axes of the (Ga,Mn)As layer. Obtained results resemble the Tunneling Anisotropic Magnetoresistance (TAMR) effect discovered recently in a normal-metal-insulator-ferromagnetic-semiconductor tunneling device .
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Presentation: Poster at E-MRS Fall Meeting 2006, Symposium E, by Mariusz Ciorga
See On-line Journal of E-MRS Fall Meeting 2006
Submitted: 2006-05-20 09:56 Revised: 2009-06-07 00:44