Facet-edge fluctuations with periphery diffusion kinetics

We investigate the novel scaling of the steps bounding a facet surrounded by a rough region. The hindered, asymmetric fluctuations can be associated with the emergence of a dominant non-linear term in the Hamiltonian governing the step fluctuations. We explore the crossover from unhindered to hindered fluctuations, calculating the growth exponent, β, with Monte Carlo simulation within the TSK model. The hindered behavior is found in the simulations when the facet-edge step is separated by fewer than six atomic spacings from the second step. Actual fluctuations are larger than in this calculation, particularly at higher temperatures, making the hindered behavior easier to observe. In addition, we discuss the possibility that volume conservation effects in nanoscale structures may cause similar confinement in non-conserved fluctuations.