SOLID-ON-SOLID MODEL WITH NEXT-NEAREST-NEIGHBOR INTERACTION FOR EPITAXIAL-GROWTH

We investigate a solid-on-solid model on two-dimensional substrates as a natural extension of the Wolf-Villain model for molecular-beam epit axial growth [D.E. Wolf and J. Villain, Europhys. Lett. 13, 389 (1990) ]. In this extended Wolf-Villain model, freshly landed atoms relax int o the local energy minima calculated within a next-nearest-neighbor ap proximation. We calculate the surface width, the correlation function, and the averaged step height and show the surface morphologies. In th e transient regime, the model can be described by the nonlinear contin uum equation proposed by Lai and Das Sarma [Z.W. Lai and S. Das Sarma, Phys. Rev. Lett. 66, 2348 (1991)]. At relatively smaller lateral size L(c) similar to 35 and earlier growth time t(c) similar to 1800 than in the original model, it shows a crossover behavior to the Edwards-Wi lkinson class, i.e., logarithmic kinetic roughening.