STABLE KINK ANTIKINK PAIRS IN BISTABLE REACTION-DIFFUSION SYSTEMS WITH STRONG NONLOCALITIES

We investigate the statics, nucleation, and dynamics of stable kink-an tikink pairs (KAP) in a one-dimensional, one-component reaction-diffus ion equation with a piecewise linear nonlinearity. The stabilization o f the KAP is due to the presence of a strongly nonlocal inhibitor. We find a saddle-node bifurcation of a metastable KAP with a separation p roportional to In L, where L is the length of the sample. The KAP beco mes globally stable at a characteristic separation proportional to roo t L. The nucleation of a KAP from the metastable uniform state differs from the case without nonlocality mainly by a change of the activatio n energy induced by the nonlocality. Furthermore, we investigate the d ynamics of the stable KAP in the presence of an external driving force and a diluted density of pointlike impurities; in particular, we deri ve expressions for the mobility and the average elongation of the KAP.