Magnetic and non-Fermi-liquid phases inCe1−xYxRhIn5

Abstract

We have investigated single-crystal samples of ${\mathrm{Ce}}_{1\ensuremath{-}x}{\mathrm{Y}}_{x}{\mathrm{RhIn}}_{5}$ by means of specific heat C, magnetic susceptibility $\ensuremath{\chi},$ and electrical resistivity $\ensuremath{\rho}$ measurements as a function of temperature T. As yttrium is substituted for cerium, the N\'eel temperature is suppressed, yielding a quantum critical point at yttrium concentration ${x}_{c}\ensuremath{\sim}0.38.$ Non-Fermi-liquid behavior (NFL) occurs in $C(T)$ and $\ensuremath{\chi}(T)$ over an extended range of yttrium concentrations above the quantum critical point $0.4l~xl~0.9$ with $C(T)$ and $\ensuremath{\chi}(T)$ displaying power law T dependences at low temperatures. Remarkably, the NFL behavior become more pronounced with increasing distance from the quantum critical point. For the samples with $0.2l~xl~0.9$ we also observe features in the specific heat and magnetic susceptibility above ${T}_{N}$ that may be due to tetragonal crystalline electric field splitting of the ${\mathrm{Ce}}^{3+}J=5/2$ multiplet with a ${\ensuremath{\Gamma}}_{7}$ ground state.