To elucidate the discrepancies in low-temperature data reported on the quantum critical heavy fermion compound ${\text{Ce}}_3{\text{Pd}}_{20}{\text{Si}}_6$ and reveal the compound’s intrinsic properties, single crystals of varying stoichiometry were grown by various techniques—from the melt and from high-temperature solutions using fluxes of various compositions. The resulting stoichiometry of the crystals as well as their physical properties show sizable dependence on the different growth techniques. The Ce content $\Delta \text{Ce}$ varies by more than $3\text{at}\text{.}\%$ among all grown single crystals. We have revealed a systematic dependence of the residual resistance ratio, the lattice parameter, the (lower) phase-transition temperature $T_L$, and the maximum in the temperature dependent electrical resistivity $T_{max}$ with $\Delta \text{Ce}$. This clarifies the sizable variation in the values of $T_L$ reported in the literature. We discuss the physical origin of the observed composition-property relationship in terms of a Kondo lattice picture. We predict that a modest pressure can suppress $T_L$ to zero and thus induce a quantum critical point.

• Received 12 March 2009

DOI:https://doi.org/10.1103/PhysRevB.80.235107