Thermoelectrical power of heavy fermion compounds

• Published in: Physica. B, Condensed matter Vol. 378; pp. 644 - 647
• Main Authors: Wilhelm, H., Zlatic, V., Jaccard, D.
• Format: Journal Article Conference Proceeding
• Language: English
• Published: Amsterdam Elsevier B.V 01.05.2006; Elsevier
• Subjects: Condensed matter: electronic structure, electrical, magnetic, and optical properties; Electron states; Electronic conduction in metals and alloys; Electronic transport in condensed matter; Exact sciences and technology; formula omitted; Physics; Scattering mechanisms and kondo effect; Strongly correlated systems; heavy fermions; Theory; Thermoelectrical power; 72.15.Jf; 75.30.Mb; 62.50 . + p; Thermoelectrical power; Theory; CeRu 2 Ge 2; Crystal field splitting; Pressure effects; Intermetallic compounds; Intermediate valence; 75.30.Mb CeRu2Ge2; Heavy fermions; Hybridization; Coulomb interaction; Repulsion interaction; Impurities; Temperature effects; Thermoelectric power; 62.50. +p; Anderson model; Energy-level splitting; Carrier density
• ISSN: 0921-4526; 1873-2135
• DOI: 10.1016/j.physb.2006.01.184

The pressure-induced changes of the thermoelectrical power of CeRu 2 Ge 2 can be well described within the single-impurity Anderson model. In this model, the experimental values of the crystal-field splittings of the 4f ground state are taken into account and it is assumed that the strong Coulomb repulsion restricts the number of 4f electrons. The calculated temperature dependence of the thermopower S ( T ) for different hybridisation strengths and temperatures above 10 K can reproduce S ( T ) of CeRu 2 Ge 2 at different pressures. This shows, that the main characteristic features observed in other Ce- and Yb-based intermetallic systems as they are tuned, either by pressure or chemical substitution, from the magnetic to the intermediate valence regime can be explained in terms of the crossover between various fixed points of the model.