TRANSPORT PHENOMENA AT ROUGH BOUNDARIES

We present a simple method describing transport processes near rough b oundaries. By a proper coordinate transformation we reduce a transport problem with rough walls to an equivalent problem with smooth flat wa lls, but with some random bulk inhomogeneities. In many cases the last problem can be treated perturbatively, leading to simple expressions for relevant transport coefficients via the correlation function of su rface inhomogeneities. We calculate diffusion and conductivity in film s, phonon, and photon diffusion, quantum corrections to conductivity, and the single-particle diffusion coefficient.