Temperature quenches in the disordered phase of a spin system

Abstract

The problem of a sudden temperature quench of a spin system is studied for the case of a two-dimensional spin-flip kinetic Ising model in zero external field. The analysis is carried out for the case where both the initial and final temperatures are in the disordered phase. The problem is analyzed with the use of a generalization of the real-space dynamic renormalization-group method. The interesting features found in studying the time-dependent structure factor are the following: (i) a nonmonotonic time dependence at finite wave numbers corresponding to "structure pulses"; (ii) a slow shift and decay in the peak of the structure factor for fixed wave number as a function of temperature; (iii) a slow approach to the final exponential relaxation to equilibrium.