AVS 53rd International Symposium
    Magnetic Interfaces and Nanostructures Thursday Sessions
       Session MI+EM-ThM

Paper MI+EM-ThM3
Epitaxial Growth, Spin Polarization, and Electrical Spin Injection from Fe(1-x)Ga(x) (001) Films on AlGaAs/GaAs(001) LEDs

Thursday, November 16, 2006, 8:40 am, Room 2006

Session: Spin Injection
Presenter: A.T. Hanbicki, Naval Research Laboratory
Authors: A.T. Hanbicki, Naval Research Laboratory
O.M.J. van 't Erve, Naval Research Laboratory
C.H. Li, Naval Research Laboratory
G. Kioseoglou, Naval Research Laboratory
M.S. Osofsky, Naval Research Laboratory
S.-F. Cheng, Naval Research Laboratory
B.T. Jonker, Naval Research Laboratory
Correspondent: Click to Email
Electrical spin injection is a prerequisite for a semiconductor spintronics technology. Spin injection into GaAs from ferromagnetic metals such as Fe via Schottky barrier tunnel contacts has been demonstrated. However, the surface emitting geometry employed to facilitate a quantum selection rule based analysis of the polarized electroluminescence (EL) produced by the spin polarized light emitting diode (spin-LED) devices necessitates the use of relatively large external magnetic fields to saturate the Fe magnetization out-of-plane. We have grown epitaxial films of Fe(1-x)Ga(x) (0 < x < 0.75), a material noted for its high magnetostriction, on AlGaAs/GaAs (001) heterostructures, and summarize the structure, magnetization, spin polarization, and results for electrical spin injection into AlGaAs/GaAs. The out-of-plane saturation field and magnetization decrease rapidly with Ga content, but the point contact spin polarization remains near that of Fe for x @<=@ 0.5. Electrical spin injection from an Fe@sub 0.5@Ga@sub 0.5@ contact produces an electron spin polarization of 30% in the GaAs at 20 K, similar to that obtained from Fe contacts, but with out-of-plane saturation fields as low as 0.4 T. This work was supported by ONR. OvE current address: Philips, Eindhoven.