Low-temperature thermal and transport properties of single-crystalline Ce$_{4}$Pt$_{12}$Sn$_{25}$

Low-temperature specific heat $C(T)$ and electrical resistivity \textit{$\rho $}($T)$ measurements have been performed on a flux-grown single-crystalline Ce$_{4}$Pt$_{12}$Sn$_{25 }$which has a body-centered cubic structure. As temperature decreased, $C(T)$ increased and showed a huge jump ($\Delta C$/$T\sim $43J/mole-K$^{2}$-Ce) at $T \quad \sim $ 0.2 K, probably due to a magnetic ordering. The entropy gain connected with the ordering reaches a half of $R$ln2 at the peak position and almost full $R$ln2 at 3 K, corresponding to the degeneracy of the fundamental crystal-field doublet. On the other hand, \textit{$\rho $}($T)$ showed metallic behavior and decreased rapidly around the ordering temperature with a clear kink. We will also discuss the results of external-field effect on this compound.