Local density of states calculation for a discrete model of a diamond single atom tip

Recent studies of field emission from wide bandgap semiconductors have concentrated on thin film and needle geometries. It has been proposed that the emission originates from localized asperities (or crystallites) on the film (which can be of nanometer or even atomic size) or from very sharp tips approaching atomic size in the case of needle geometry. The quantity important in determining the origin of the tunneling electron states is a density of states function. In the present work we have calculated the local density of states (LDOS) at an atomically sharp diamond asperity (or tip) using a tight binding model.