Field-tuned critical fluctuations in YFe2Al10: Evidence from magnetization,27Al NMR, and NQR investigations

Abstract

We report magnetization, specific heat, and NMR investigations on YFe${}_{2}$Al${}_{10}$ over a wide range of temperature and magnetic field and zero field (NQR) measurements. Magnetic susceptibility, specific heat, and spin-lattice relaxation rate divided by $T(1/{T}_{1}T)$ follow a weak power law ($\ensuremath{\sim}$${T}^{\ensuremath{-}0.4}$) temperature dependence, which is a signature of the critical fluctuations of Fe moments. The value of the Sommerfeld-Wilson ratio and the linear relation between $1/{T}_{1}T$ and $\ensuremath{\chi}$ suggest the existence of ferromagnetic correlations in this system. No magnetic ordering down to 50 mK in ${C}_{p}(T)/T$ and the unusual $T$ and $H$ scaling of the bulk and NMR data are associated with a magnetic instability which drives the system to quantum criticality. The magnetic properties of the system are tuned by field wherein ferromagnetic fluctuations are suppressed and a crossover from quantum critical to Fermi-liquid behavior is observed with increasing magnetic field.