Fermi Surface of LaRu2Ge2and CeRu2Ge2within Local-Density Band Theory

Abstract

We derive the Fermi surface for LaRu 2 Ge 2 by a self-consistent relativistic APW method within the framework of a local-density approximation. The Fermi surfaces thus obtained are composed of four hole sheets and an electron sheet, all of which have no open orbits. The Fermi surface topology is consistent with the experimental results for the high-field transverse magnetoresistance. These Fermi surfaces explain reasonably well the absolute magnitude and the angular dependence of the de Haas-van Alphen (dHvA) frequency-branches. Moreover, we use the theoretical Fermi surface of LaRu 2 Ge 2 to re-examine an origin of the dHvA frequency-branches for a ferromagnetic CeRu 2 Ge 2 regarded as non-Kondo-lattice system.