Exchange coupling in Eu compounds

Jan Kunesˇa,b, , Warren E. Picketta

aDepartment of Physics, University of California Davis, One Shields Avenue, Davis CA 95616, USA

bInstitute of Physics, AS CR, Prague, Czech Republic

Abstract 

Using ab initio electronic structure calculations employing the LDA+Umethod we have investigated the exchangecoupling in materials containing Eu in Eu2+formal valency including: (i) insulating ferromagnets (EuO, EuS, EuSe,EuTe), and (ii) elemental metal BCC Eu. The total energies calculated with constrained magnetic structures weremapped on the Heisenberg Hamiltonian in order to investigate the thermodynamic properties. The mechanisms ofinter-site exchange, which differ between the studied systems, are discussed.

http://yclept.ucdavis.edu/Publ/EuExchCoupl.pdf