Exchange interactions, spin waves, and transition temperatures in itinerant magnets

0178060 - UFM-A 20033078 RIV GB eng J - Článek v odborném periodiku
Turek, Ilja - Kudrnovský, Josef - Drchal, Václav - Bruno, P.
Exchange interactions, spin waves, and transition temperatures in itinerant magnets.
Psi-k Newsletter. Roč. 1, č. 59 (2003), s. 112-147
Grant CEP: GA ČR GA106/02/0943; GA AV ČR IAA1010203
Výzkumný záměr: CEZ:AV0Z2041904
Klíčová slova: exchange interactions * itinerant magnetism
Kód oboru RIV: BM - Fyzika pevných látek a magnetismus
http://psi-k.dl.ac.uk/psi-k/newsletters.html

The contribution reviews an ab initio two-step procedure to determine exchange interactions, spin-wave spectra, and thermodynamic properties of itinerant magnets. In the first step, the selfconsistent electronic structure of a system is calculated for a collinear spin structure at zero temperature. In the second step, parameters of an effective classical Heisenberg Hamiltonian are determined using the magnetic force theorem and the one-electron Green functions. The Heisenberg Hamiltonian and methods of statistical physics are employed in subsequent evaluation of magnon dispersion laws, spin-wave stiffness constants, and Curie/Neel temperatures. Applicability of the developed scheme is illustrated by selected properties of various systems like transition and rare-earth metals, disordered alloys including diluted magnetic semiconductors, ultrathin films, and surfaces.
Trvalý link: http://hdl.handle.net/11104/0074954