Field Emission from Metals in Strong Electric Fields

In the framework of the local density-functional formalism and the model of a homogeneous positive background of a lattice, a self-consistent model of the field emission from a metal in a strong electric field has been proposed and developed. This model has made it possible to do away with some "classical" assumptions and suppositions that were used in the construction of the Fowler-Nordheim theory and its consequences. In the framework of the fully quantum model proposed, self-consistent calculations of the electronic wave functions and of the effective single-electron potential in view of multiparticle effects in a local approximation have shown that the potential barrier at the metal-vacuum interface is much wider and higher than in the case of the conventional approach. This, in turn, results in significantly lower field-emission current densities and in a strongly pronounced deviation from the Fowler-Nordheim straight line in the region of strong fields