Dynamics of an Ising Spin-Glass in the Vicinity of the Spin-Glass Temperature

Abstract

The dynamics of the short-range Ising spin-glass ${\mathrm{Fe}}_{0.5}$${\mathrm{Mn}}_{0.5}$Ti${\mathrm{O}}_{3}$ has been investigated with a SQUID magnetometer. The dynamic spin-correlation function, $q(t)$, as reflected in low-field ac susceptibility and time-dependent magnetization measurements, was studied in the time interval ${10}^{\ensuremath{-}6}$-${10}^{4}$ sec. The functional form of $q(t)$ shows a remarkable agreement with the results obtained from Monte Carlo simulations on a three-dimensional Ising spin-glass. The temperature dependence of the relaxation times above the spin-glass temperature is well described by conventional power-law scaling.