Regensburg 2004 – wissenschaftliches Programm

Bereiche | Tage | Auswahl | Suche | Downloads | Hilfe

MA: Magnetismus

MA 13: Poster:Schichten(1-23),Spinabh.Trsp(24-41),Exch.Bias(42-56),Spindyn.(57-67),Mikromag.(68-76),Partikel(77-90),Spinelektr.(91-97),Elektr.Theo.(98-99),Mikromag+PhasÜ+Aniso.(100-105),Magn.Mat.(106-118),Messmethod.(119-121),Obflm.+Abbverf.(122-123)

MA 13.13: Poster

Dienstag, 9. März 2004, 15:00–19:00, Bereich A

Magnetic anisotropy in Co₂MnSi films grown by PLD on GaAs(001) — •W. Wang, Y. Lu, J. Barthel, H. Meyerheim, M. Przybylski, and J. Kirschner — Max-Planck-Institut für Mikrostrukturphysik, Weinberg 2, 06120 Halle

Spin injection efficiency from a ferromagnetic (FM) ohmic contact into a semiconductor is expected to improve as the FM spin polarization nears 100%. Half metallic FMs, like Co₂MnSi, are expected to meet this requirement. We report on the magnetic properties of Co₂MnSi thin films grown by the Pulsed Laser Deposition (PLD) technique on GaAs(001). The best crystallographic quality of the films has been achieved after deposition at 450K. The films exhibit in-plane uniaxial magnetic anisotropy with the easy axis of magnetization along the [1-10] direction. When the field is applied under an angle to [1-10], magnetization reversal proceeds in two steps: at low fields the magnetization is oriented along [1-10] and then switches to [110] at higher fields. This is clearly seen within the MOKE hysteresis loops, which reflect two-step magnetization projection to the field direction. The anisotropy depends strongly on the film thickness and on temperature. At the film thickness of about 60Å, the energy minimum for the magnetization directed along [110] is not deep enough to be pronounced at room temperature. In this case, the magnetization initially points along [1-10], and with increasing field rotates to the field direction.