Coarse-graining a restricted solid-on-solid model.
A procedure suggested by Vvedensky for obtaining continuum equations as the coarse-grained limit of discrete models is applied to the restricted solid-on-solid model with both adsorption and desorption. Using an expansion of the master equation, discrete Langevin equations are derived; these agree quantitatively with direct simulation of the model. From these, a continuum differential equation is derived, and the model is found to exhibit either Edwards-Wilkinson or Kardar-Parisi-Zhang exponents, as expected from symmetry arguments. The coefficients of the resulting continuum equation remain well-defined in the coarse-grained limit.
Lazarides
Achilleas
A
Department of Mathematics, Imperial College, 180 Queen's Gate, London SW7 2BZ, United Kingdom. achilleas.lazarides@imperial.ac.uk