大型放射光施設 SPring-8

Speaker : Prof. Gertrud Zwicknagl

Language : ENGLISH

Affiliation : Technische Universität Braunshweig

Title : Heavy fermions in YbRh2Si2: Influence of magnetic field and elevated temperature

Abstract :
The temperature versus magnetic field phase diagram of the heavy fermion compound YbRh2Si2 exhibits numerous anomalies. The focus of the calculations presented here is the evolution of the heavy quasiparticles in high magnetic fields and at elevated temperatures where the moment screening due to the Kondo effect is weakened. The quasiparticle bands in high magnetic fields are determined by means of the Renormalized Band method. The progressive de-renormalization of the quasiparticles in the magnetic field as well as the many-body enhancement of the Zeeman splitting are accounted for using field-dependent quasiparticle parameters deduced from Numerical Renormalization Group studies. The calculations predict Lifshitz transitions at well-defined values of the external magnetic field which have been observed in various transport properties. Preliminary calculations of the evolution of the 4f-spectral function with temperature are discussed. The results are compared with recent ARPES data.

担当者 : 藤森 伸一
Mail : fujimori@spring8.or.jp
PHS : 3914