Search for pressure-induced quantum criticality in YbFe2Zn20

Abstract

Electrical transport measurements of the heavy-fermion compound YbFe${}_{2}$Zn${}_{20}$ were carried out under pressures up to 8.23 GPa and down to temperatures of nearly 0.3 K. The pressure dependence of the low-temperature Fermi-liquid state was assessed by fitting $\ensuremath{\rho}(T)={\ensuremath{\rho}}_{0}+A{T}^{n}$ with $n=2$ for $T<{T}_{\mathrm{FL}}$. Power-law analysis of the low-temperature resistivities indicates $n=2$ over a broad temperature range for $P\ensuremath{\lesssim}5$ GPa. However, at higher pressures, the quadratic temperature dependence is only seen at the very lowest temperatures, and instead shows a wider range of $n<2$ power-law behavior in the low-temperature resistivities. As pressure was increased, ${T}_{\mathrm{FL}}$ diminished from $\ensuremath{\sim}$11 K at ambient pressure to $\ensuremath{\sim}$0.6 K at 8.23 GPa. Over the same pressure range, the $A$ parameter increased dramatically with a functional form of $A\ensuremath{\propto}{(P\ensuremath{-}{P}_{\mathrm{c}})}^{\ensuremath{-}2}$ with ${P}_{\mathrm{c}}\ensuremath{\simeq}9.8$ GPa being the critical pressure for a possible quantum critical point.