Dresden 2017 – wissenschaftliches Programm
TT 41.11: Vortrag
Mittwoch, 22. März 2017, 12:15–12:30, HSZ 204
Signature of frustrated moments in quantum critical CePd1−xNixAl — Akito Sakai1, Stefan Lucas2, Zita Huesges2, Kai Grube3, Philipp Gegenwart1, Oliver Stockert2, Hilbert v. Löhneysen3, and •Veronika Fritsch1 — 1EP 6, Electronic Correlations and Magnetism, Augsburg University, Germany — 2Max Planck Insitute for Chemical Physics of Solids, Dresden, Germany — 3Institute for Solid State Physics and Physics Institute, Karlsruhe Institute of Technology, Germany
Magnetic frustration suppresses long-range magnetic order despite the presence of strong magnetic couplings. This results in exotic ground states, where the spins can fluctuate down to zero temperature. However, metallic materials that simultaneously exhibit magnetic frustration and a strong coupling between the magnetic moments and the conduction electrons, are quite scarce.
The here presented CePdAl is a system were the Kondo effect and magnetic frustration coexist. It can be tuned across a quantum critical point by substitution of Pd with approximately 14% of Ni. Furthermore, field-induced quantum criticality can be observed in CePd1−xNixAl. We have investigated single crystals with Ni concentrations 0 ≤ x ≤ 0.16. In addition to the generic signatures of quantum criticality a unique thermodynamic feature of the frustrated moments, i.e. an additional contribution to the magnetic Grüneisen paramter, is discovered .
 A. Sakai et al., ArXiv:1609.00816 [cond-mat.str-el] (2016).