External-field-enabled surface nanopattern engineering (a perspective on the article "current-driven morphological evolution of single-layer epitaxial islands on crystalline substrates" by D. Dasgupta, G. I. Sfyris and D. Maroudas)

A perspective on an article authored by D. Dasgupta, G. I. Sfyris and D. Maroudas, titled, 'Current-driven morphological evolution of single-layer epitaxial islands on crystalline substrates' is presented. The Letter by Dasgupta and researchers takes important steps in this surface nanoengineering direction. The first is in broadening the scope of existing continuum models for the current-driven dynamics of single-layer epitaxial islands; coherently strained heteroepitaxial islands are now also included in the formulation, and the effect of different crystallographic orientations and different strain misfits can be quantitatively studied. Based initially on steadily migrating islands, the authors propose an island shape factor; when scaled with this factor, the relation between the island velocity and the inverse of the island size becomes cleanly linear over the entire regime of island sizes and island steady and non-steady shapes that the authors have studied.