FROM QUENCHED TO ANNEALED - A STUDY OF THE INTERMEDIATE DYNAMICS OF DISORDER

A model spin system with disorder is examined. The disorder is not necessarily quenched but it may evolve on a time scale that can be tuned. The annealed and quenched cases obtained as limiting cases are, respectively, the infinite-range Ashkin-Teller (P = 2 colours) model and the Hopfield neural net (finite number of patterns P = 2). The intermediate-dynamics model behaves like a Hopfield associative memory on short time scales and like an Ashkin-Teller system in the long run. The time evolution of the order parameters is obtained from the master equations in the mean-field approximation.