Thursday 14.06.12, 15:15-16:15 SR 4


Three intriguing cases of metamagnetic transitions in heavy-fermion systems: CeTiGe, CeRu2Si2 and YbRh2Si2.

Manuel Brando, Max-Planck Institut CPfS, 15h15-16h15 SR4

I will present an overview of recent transport and thermodynamic experiments on the metamagnetic heavy-fermion systems CeTiGe, CeRu2Si2 and YbRh2Si2. The type of metamagnetism in these three compounds is different. In CeTiGe the magnetic field induces a pronounced 1st-order phase transition characterized by a large step in magnetization whereas in CeRu2Si2, which is a system close to a quantum critical endpoint, a Lifshitz transition has been considered. Finally, in YbRh2Si2 the magnetization shows a kink at the critical field B* and our recent experiments strong indicate that a Lifshitz transition takes place at B* as a consequence of a van-Hove singu- larity. I will summarize part of the results published in the following references:
M. Deppe et al. , PRB 85 060401 (R) (2012)
F. Weickert et al. , PRB 81 134438 (2010)
H. Pfau et al., PRB 85 035127 (2012)