1204.5574 (Noriko Akutsu)

Inhibition of step movements near equilibrium for sticky steps    [PDF]

Noriko Akutsu

Using a Monte Carlo method on a restricted solid-on-solid model with a point-contact type step-step attraction (p-RSOS model), we show that, at low temperature and near equilibrium, there is an inhibition of giant step movements and a self-pinning of steps. The origin of the inhibition of the step movements is the `step faceting', which is caused by a singularity in the anisotropic surface free energy (surface tension). We show that the singularity in the surface free energy results from the sticky steps by using a statistical-mechanical calculation. Further, from the calculation of a surface stiffness tensor, we show that `step droplets', which are locally merged steps and are caused by a singularity in the surface free energy, roughen the vicinal surface. Near equilibrium, however, the step droplets slow down the step velocity due to the diminishment of kinks in the steps. We present an equation for the transport coefficient, which reproduces the Monte Carlo results.

View original: http://arxiv.org/abs/1204.5574