Regensburg 2010 – scientific programme

Parts | Days | Selection | Search | Downloads | Help

MA: Fachverband Magnetismus

MA 33: Poster II

MA 33.69: Poster

Friday, March 26, 2010, 11:00–14:00, Poster B1

Influence of band parameters on spin-transfer torque in tunnel junctions: model calculations — •Asma Heena Khalil and Christian Heiliger — . Physikalisches Institut, Justus Liebig University Giessen, D-35392, Germany

Investigations of the spin-transfer torque in magnetic tunnel junctions have come into focus of current research because these devices are a basis of magnetic random access memories (MRAM). In particular, one is interested in the bias voltage dependence of this torque. For a Fe/MgO/Fe system our ab initio calculations [1] are supported by experimental data [2] where the bias dependence seems to be linear. On the other hand results of simple-band model calculations show deviations from this behavior [3]. In this contribution we study the in-plane spin-transfer torque in magnetic tunnel junctions for different band fillings and exchange splittings. For parameters that reproduce the important features of the Fe band structure, the results are in agreement with experimental data as well as with ab initio calculations.

[1] C. Heiliger and M.D. Stiles, Phys. Rev. Lett. 100, 186805 (2008).

[2] J. C. Sankey, Y.-T. Cui, J. Z. Sun, J. C. Slonczewski, R. A. Buhrman, D. C. Ralph, Nature Phys. 4, 67, 2008

[3] I. Theodonis, N. Kioussis, A. Kalitsov, M. Chshiev, and W. H. Butler, Phys. Rev. Lett. 97, 237205 (2008).