First-principles calculations of transport and magnetic properties of rare-earth materials

ABSTRACT We describe the applications of rst-principles calculations to the analysis of transport and magnetic propertiesof rare-earth materials. The rst application is a detailed calculation of the spin-disorder resistivity of heavyrare-earth metals in the Gd-Tm series. The crystallographic anisotropy of the spin-disorder resistivity agreeswell with experiment, but its magnitude is signi cantly underestimated. Possible origins of this discrepancy arediscussed. In the second part we analyze the exchange interaction in Gd-doped EuO using a magnetostructuralcluster expansion based on the ab initio total energies. The calculated Curie temperature has a broad maximumextending over 10-20% Gd concentration and reaching approximately 150 K. 1. INTRODUCTION Rare-earth materials have long been a subject of extensive fundamental research. 1{3 The key feature controllingtheir physical properties is the existence of partially lled, strongly correlated and well localized 4 f electronshells, which interact with the itinerant (valence and/or conduction) electrons through on-site exchange inter-action. With some notable exceptions, the hybridization of 4 f electrons is usually weak. The on-site exchangeinteraction gives rise to indirect (RKKY) exchange,