Numeerisen analyysin ja laskennallisen tieteen seminaari

11.4.2005  klo 14.15  U322

Marko Rusanen, Fysiikan laboratorio
Rate equation modeling of surface growth phenomena

Surfaces of materials have been a subject of intensive research during past few decades. In addition to apparent technological applications surface growth phenomena provide excellent examples of non-equilibrium processes in statistical physics. Novel experimental methods for measuring and imaging nanoscale surface structures have inspired also theoretical and computational studies to explain and predict the properties of nanostructures. These nanostructures can be manufactured by growth of a material on top of a surface of another. By understanding the microscopic growth mechanisms one can obtain realiable predictions of experimental systems. One way among the others to model surface growth is rate equations. These form a set of coupled first order differential equations describing the time evolution of e.g. densities of atom clusters. Solving this set can be a formidable task due to various time scales in the problem, and sometimes stochastic integration methods turn out to be practical. These methods apply equally well in any other problem involving coupled differential equations. I will describe rate equation modeling both in general and applied in surface growth with a specific simulation method.