Stochastic dynamics in polymer translocation

The dynamics of ideal polymer chains crossing a potential barrier in the presence of a metastable state is studied at different noise intensities. The diffusive motion of the polymer in a two-dimensional domain is modelled by two coupled Langevin equations. The Rouse model for a flexible polymer is adopted to take into account the interactions between adjacent monomers. We have analyzed the mean first passage time of the polymer centre of inertia, and its standard deviation, as a function of the noise intensity. A nonmonotonic behavior is observed, as a noise induced effect on the mean translocation time. We have also investigated the role of the polymer length and of the initial spatial distribution of the chain monomers.