Pattern Formation in Erosion-Redeposition Processes

The effects of erosion-redeposition (ER) processes arising in plasma-surface interactions (PSI) is investigated by a 2-D computational model. The corresponding pattern formation (PF) process is governed by nonlinear particle-diffusion equations, with source terms in which different particle interactions like ionization, recombination, charge exchange, particle reflection at the surface, etc., may be taken into account. The model presented here combines diffusion-limited aggregation (DLA) to compute redeposition and anti-DLA for erosion patterns. Resulting PF gives a reasonable description of nonlinear diffusion of charged particles with and without the presence of a magnetic field, in regions closest to plasma-facing materials and redeposition of neutral particles ejected from the wa