Take a sneak peek at the new NIST.gov and let us know what you think!
(Please note: some content may not be complete on the beta site.).
NIST Authors in Bold
|Author(s):||Ion Garate; Keith Gilmore; Mark D. Stiles; Allan H. MacDonald;|
|Title:||Non-Adiabatic Spin Transfer Torque in Real Materials|
|Published:||March 16, 2009|
|Abstract:||The motion of simple domain walls and of more complex magnetic textures in the presence of a transport current is described by the Landau-Lifshitz-Slonczewski (LLS) equations. Predictions of the LLS equations depend sensitively on the ratio between the dimensionless material parameter β which characterizes non-adiabatic spin-transfer torques and the Gilbert damping parameter α. This ratio has been variously estimated to be close to 0, close to 1, and large compared to 1. By identifying β as the influence of a transport current on α, we derive a concise, explicit and relatively simple expression which relates β to the band structure and Bloch state lifetimes of a magnetic metal. Using this expression we demonstrate that intrinsic spin-orbit interactions lead to intra-band contributions to β which are often dominant and can be (i) estimated with some confidence and (ii) interpreted using the ``breathing Fermi surface'' model.|
|Citation:||Physical Review B (Condensed Matter and Materials Physics)|
|Keywords:||Spin-transfer torque, Magnetic damping, Magnetization dynamics, Adiabatic, Spin-orbit coupling, Domain wall, Spin current|
|PDF version:||Click here to retrieve PDF version of paper (317KB)|