Tight-binding parameters for Wurtzite-Zinc Blende crystal phase heterostructures

Models of materials are used to explain observed properties as well as predict novel behavior. One such model is the Tight-Binding model which aims to describe the electronic properties of a substance, like a molecule or a crystal, by thinking of electrons as typically staying very close to atoms (Tightly Bound) but allowed move to nearby atoms as if by ‘hopping’. The electronic parameters that define this model are determined for a particular type of crystal by finding the parameter values that produce results in close agreement with experimental observations. If the Tight-Binding model can describe this crystal when it is deformed slightly or butted up against another material to create an interface, we call the model ‘Transferable’. An extension of the idea of transferability is to try to use the model in another type of closely related crystal called a polytype, which are crystals that vary only slightly in the way the atoms are bonded. These crystal cousins are often observed during the growth of very narrow pillars called nanowires. While polytype transferability sounds reasonable, certain approximations made to simplify the original model prevent an accurate description of these closely related crystals. It is the aim of this work to determine a suitable set of parameters for some of these polytypes to aid in the understanding of these structures and development of new devices.