Solution of counter diffusion problem with position dependent diffusion coefficent by using variational methods

Comparison between fixed and Gaussian steplength in Monte Carlo simulations for diffusion processes

“…In some systems the variability of the diffusion coefficient is due to a position-dependent random force such as the one studied in [4], or due to a variation of the concentration [5]. It is possible to generate a drift current in the absence of any external force or concentration gradient using a spatial dependent diffusion coefficient, as shown in [6].…”