NUCLEATION OF KINKS AT GRAIN-BOUNDARIES

The decay of metastable states in spatially one-dimensional systems by kink nucleation at the sample boundaries is investigated for a specif ic bistable reaction-diffusion system. An expression for the nucleatio n rate is derived in the framework of multidimensional Kramers theory, and the dependence of the rate on the boundary conditions is discusse d. It turns out that the question whether homogeneous kink nucleation in the built or heterogeneous kink nucleation at the sample boundary p redominates depends on the specific type of the boundary.