Tuning the electronic structure of solids with nanometer-sized microstructures

Abstract

Most materials studied and/or used technologically today are electrically neutral,i.e. the positive and negative electric charges are balanced. Limited attention has been paid so far to the option of influencing the properties of materials by deviating from charge neutrality. In fact, solids with nanometer-sized microstructures may open the way to generate materials with an excess or a deficit of electrons or holes of up to about 0.3 electrons/holes per atom. Such deviations from charge neutrality may be achieved either by means of an externally applied voltage or by space charges at interfaces between materials with different chemical compositions (or combinations of both). As many properties of solid materials depend on their electronic structure, significant deviations from charge neutrality result in materials with new, yet mostly unexplored properties such as modified electric, ferromagnetic, optical etc. properties as well as alloys of conventionally immiscible components or materials with new types of atomic structures. Existing and conceivable new technological applications of solids deviating from charge neutrality are discussed.