PHASE ORDERING OF CONSERVED VECTORIAL SYSTEMS WITH FIELD-DEPENDENT MOBILITY

The dynamics of phase-separation in conserved systems with an O(N) con tinuous symmetry is investigated in the presence of an order-parameter -dependent mobility M{phi} = 1-a phi(2). The model is studied analytic ally in the framework of the large-N approximation and by numerical si mulations of the N=2, N=3, and N=4 cases in d=2, for both critical and off-critical quenches. We show the existence of a universality class for a=1 characterized by a growth law of the typical length L(t)simila r to t(1/z) with dynamical exponent z=6 as opposed to the usual value z=4, which is recovered for a<1. [S1063-651X(98)16609-6].