Effective magnetic Hamiltonians from ﬁrst principles
Institute of Physics AS CR, Na Slovance 2, CZ-182
8, Czech Republic
2 Department of Condensed Matter Physics, Charles University, CZ-121 16, Praha 2, Czech Republic
a e-mail: firstname.lastname@example.org
We construct eﬀective magnetic Hamiltonians by using the ﬁrst-principles electronic-structure calculations. These Hamiltonians are used to determine the ground state of solids and nanostructures, and, at T > 0, using the methods of statistical mechanics, also their magnetic properties as a function of temperature. The present approach is highly ﬂexible and it makes possible to ﬁnd magnetic structure of complex systems with the accuracy of ab initio methods. As illustrations we show (i) how the magnetic structure at T = 0 and at T > 0 can be determined for systems with anisotropic exchange and for systems with several sublattices, (ii) why the magnetic moment in fcc-nickel is unstable upon reversal, and (iii) how to calculate the size of magnetic moment in fcc-Ni at the Curie temperature, which is important for explanation of the spin-disorder resistivity in Ni.
© Owned by the authors, published by EDP Sciences, 2013