SPEAKER: Anastasios Matzavinos, Brown University
TITLE: Mesoscopic modeling of polymer transport in an array of entropic barriers
In this talk, we discuss dissipative particle dynamics (DPD) simulations of biological polymers (e.g., DNA molecules) dispersed by a pressure-driven fluid flow across a periodic array of entropic barriers. We compare our simulations with nanofluidic experiments, which show polymers transitioning between various types of behaviors as pressure increases, and discuss physical insights afforded by the ability of the DPD method to model flows at the nanoscale. We also consider anomalous diffusion phenomena that emerge in both experiment and simulation, and illustrate similarities between this system and Brownian motion in a tilted periodic potential. Finally, we formulate and analyze a continuous-time Markov process modeling the motion of the polymer across the entropic barriers. Our main result is a functional central limit theorem for the position of the polymer with an explicit formula for the effective diffusion coefficient in terms of the parameters of the model. A law of large numbers for the asymptotic velocity and large deviation estimates are also obtained.