Critical Relaxation in Dipolar Ising Model at Marginal Dimension

Abstract

The equation of motion for a dipolar Ising Model at a marginal dimension d=3 is studied on the basis of the renormalized field theory. It is shown that the temperature dependence of a nonlinear relaxation time t^(nl) is related to a linear one t^(l) as t^(nl)=t^(l)M_s⁺, where M_s⁺ is defined as the spontaneous magnetization at the temperature T_c−|τ| irrespective of the sign of the renormalized temperature difference τ=T−T_c.