Interfacial coarsening dynamics in epitaxial growth with slope selection

We investigate interfacial dynamics of molecular-beam epitaxy (MBE) growth in the presence of instabilities inducing formation of pyramids. We introdu ce a kinetic scaling theory which provides an analytic understanding of the coarsening dynamics laws observed in numerous experiments and simulations of the MBE. We address MBE growth on crystalline surfaces with different sy mmetries in order to explain experimentally observed differences between th e growth on (111) and (001) surfaces and understand the coarsening exponent s measured on these surfaces. We supplement our kinetic scaling theory by n umerical simulations which document that the edges of the pyramids, forming a network across the growing interface, are essential for qualitative unde rstanding of the coarsening dynamics of molecular-beam epitaxy.