Critical Dynamics of Ferromagnets in6−εDimensions

Abstract

The critical dynamics of a model isotropic ferromagnet is studied in $6-\epsilon$ dimensions both above and below $T_c$. The renormalization group and the characteristic frequency exponent $z$ are determined to order $\epsilon$. Implications of the renormalization group are discussed. A direct calculation of the dynamic response function to order $\epsilon$ shows many interesting features, especially for $T<\mathrm{}{T}_c$.