Regensburg 2010 – wissenschaftliches Programm

Bereiche | Tage | Auswahl | Suche | Downloads | Hilfe

TT: Fachverband Tiefe Temperaturen

TT 26: CE: Heavy Fermions

TT 26.16: Vortrag

Mittwoch, 24. März 2010, 18:15–18:30, H21

Charge Fluctuations and the Valence Transition in Yb under Pressure — Erik R. Ylvisaker¹, •Jan Kuneš², Andrew K. McMahan³, and Warren E. Pickett¹ — ¹Department of Physics, University of California, Davis, California, USA — ²Theoretical Physics III, Center for Electronic Correlations and Magnetism, Institute of Physics, University of Augsburg, Augsburg, Germany — ³Lawrence Livermore National Laboratory, Livermore, California, USA

Materials, whose atomic state cannot be approximated by a single Slater determinant, are said to have fluctuating or intermediate valence. Using dynamical mean-field theory we investigate the physics of elemental Yb, which exhibits a valence transition under pressure accompanied by a crossover from the fluctuating to the intermediate valence behavior. By comparison to other rare-earth materials (Ce, Nd, Pr) we show that fluctuating and intermediate valence regimes can be distinguished by the charge susceptibility. A large charge susceptibility can explain the softness of Yb in the valence transition region.