Distributions of Steps on Vicinal Surfaces: Renewed Interest

Abstract

  Recent experiments on curved crystals have created renewed interest in the properties of vicinal (misoriented from high-symmetry). We begin with a review of results for close-packed, straight steps. While the overall picture is rather familiar, we emphasize various noteworthy subtleties as well as use of a generalization of the Wigner surmise. The curved crystal experiments consider not just these steps but also steps that are fully kinked, zigzagged, half way in polar angle between two orientations with straight steps. The terrace-width distribution (TWD) does not satisfy the scaling relations routinely seen for straight steps. We discuss differences in the stiffness and the issues that arise in extending theoretical analysis of the TWD to these vicinal surfaces. There are several open issues that merit attention to address these questions.