Defect-deformational Kuramoto-Sivashinsky equation and formation of surface nano- and microstructures under the laser and ion-beam irradiation

Systematic numerical investigation of recently derived isotropic 2D defect-deformational (DD) Kuramoto-Sivashinsky (KS) equation that desribes the surface relief of the stressed nanolayer with nonequilibrium mobile point defects is carried out. It is demonstrated that the DDKS equation describes the formation of the surface DD structures of three main types: lamellar-like structures, and disordered and hexagonally ordered ensembles of nanoparticles. The generalization of the DDKS equation to the anisotropic diffusion of surface defects is performed and the numerical solution to the derived anisotropic DDKS equation is obtained to describe the formation of 1D surface DD ripples. The calculated results are compared with the experimental data on the formation of surface nano- and microstructures on solid surface under the laser and ion-beam irradiation.