Structural and transport studies of stoichiometric and off-stoichiometric thin films of the full Heusler alloy Co2MnSi

Co2MnSi Heusler alloy thin films have been grown by cosputtering from three elemental targets. Changes in growth temperature and stoichiometry affect the film texture and the temperature dependence of the resistivity. However, the spin polarization of the transport current is insensitive to these changes, being of the order of 54% as determined by point contact Andreev reflection spectroscopy. Stoichiometric films are single phase, have a strong (110) texture, and a saturation magnetization of 1007 emu/cc (4.95 mu(B)/formula unit) at 10 K. (C) 2004 American Institute of Physics.