Pronounced first-order metamagnetic transition in the paramagnetic heavy-fermion system CeTiGe

Abstract

We report on the observation of large, steplike anomalies in the magnetization (ΔM=0.74μ B/Ce), in the magnetostriction (Δl/l 0=2.0×10 -3), and in the magnetoresistance in polycrystals of the paramagnetic heavy-fermion system CeTiGe at a critical magnetic field μ 0H c-12 T at low temperatures. The size of these anomalies is much larger than those reported for the prototypical heavy-fermion metamagnet CeRu 2Si 2. Furthermore, hysteresis between increasing and decreasing field data indicate a real thermodynamic, first-order type of phase transition, in contrast to the crossover reported for CeRu 2Si 2. Analysis of the resistivity data shows a pronounced decrease of the electronic quasiparticle mass across H c. These results establish CeTiGe as a rare metamagnetic Kondo-lattice system, with an exceptionally large, metamagnetic transition of first-order type at a moderate field. © 2012 American Physical Society.