STRETCHED EXPONENTIAL DECAY AT INTERMEDIATE TIMES IN THE ONE-DIMENSIONAL ISING-MODEL AT LOW-TEMPERATURES

The linear response function of energy to a temperature perturbation is studied for the Glauber one-dimensional kinetic Ising model. The relaxation is exponential in the limits of short and long times at any temperature. Nevertheless, while at high temperatures the relaxation is essentially dominated by the first exponential, it is analytically shown that as the temperature decreases, an intermediate time window develops inside which the response function decays as exp[-(t/tau)1/2]. For T-->0, this function describes the relevant part of the relaxation.