The emergence of novel properties in nanostructures can be related to various factors, important ones being electron confinement and lower atom coordination. The goals of this FWP are two-fold, first to grow epitaxially controllable nanostructures and second to use their novel, selectable properties on several technologically important problems. Achieving these goals it is also essential to find ways to tune atomistic processes (diffusion, adsorption) and use them to grow perfect nanoscale patterns easily and in short times. Such studies have been carried out in several specific systems. Understanding metal growth on graphene, graphite and other carbon coated substrates is one of the areas of interest because graphene based devices require stable metal contacts of low electrical resistance. Novel graphene properties can emerge after metal intercalation. Robust ways were found to speed up adatom diffusion, from the electric field generated in regions of different workfunction on metal islands or when 2-dimensional metallic overlayers become extremely mobile after compressed to densities higher than their crystalline densities. Understanding the growth mechanism for defect-free nanostructures with high and tunable aspect ratios on carbon coated surfaces is relevant for magnetic and optoelectronic applications.
This research is supported by the U.S. Department of Energy, Office of Basic Energy Sciences, Division of Materials Sciences and Engineering.