Berlin 2012 –
wissenschaftliches Programm
O 91.54: Poster
Freitag, 30. März 2012, 11:00–14:00, Poster A
Magnon dispersion relation in adiabatic spin approximation — •Christian Franz and Christian Heiliger — I. Physikalisches Institut, Justus-Liebig-Universität, Gießen, Deutschland
The adiabatic approximation is used to separate the fast electronic degrees of
freedom from the slow magnetic ones. A single magnetic moment is assigned to
each atom in an itinerant ferromagnet. The interaction of these moments can be
described by an effective Heisenberg model.
|
H = − | | Ji,j | | i · | | j − | |
| | Siz
(1) |
The exchange parameters of this model are obtained from ab
initio calculations by applying the magnetic force theorem. The magnon
dispersion and various physical parameters as the spin-wave stiffness and the
Curie temperature can be determined within this model. We perform this
calculations several systems and find result in good agreement with
experimental and other theoretical results. This is the first step in including magnons and the electron-magnon interaction in transport calculations.
