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 ($\ensuremath{\Delta}M=0.74\phantom{\rule{0.28em}{0ex}}{\ensuremath{\mu}}_{\mathrm{B}}/$Ce), in the magnetostriction ($\ensuremath{\Delta}l/{l}_{0}=2.0\ifmmode\times\else\texttimes\fi{}{10}^{\ensuremath{-}3}$), and in the magnetoresistance in polycrystals of the paramagnetic heavy-fermion system CeTiGe at a critical magnetic field ${\ensuremath{\mu}}_{0}{H}_{c}\ensuremath{\approx}12$ T at low temperatures. The size of these anomalies is much larger than those reported for the prototypical heavy-fermion metamagnet CeRu${}_{2}$Si${}_{2}$. 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${}_{2}$Si${}_{2}$. 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.