Nanoscopic semiconductor quantum rings

Abstract

Semiconductor quantum rings are a particular type of toroidal shaped quantum dot-like structures. As in quantum dots, the number of carriers confined within these structures can be controlled one by one, and to a large extent their electronic and optical properties can be tailored, which makes them highly promising candidates for the eventual construction of nanoelectronic devices. However, the electronic structure and magnetic response of quantum rings is very different from that of quantum dots, owing to their doubly-connected topology. Over the last decade, much effort has been put into understanding the fundamental features of these structures, and comparing them to the well-known case of quantum dots. In this report, we present an overview of the progress in the understanding of self-assembled nanorings through our theoretical research related to experimental evidences. We have studied several properties of quantum rings, from their energy structure, to optical spectroscopy and the formation of quantum ring molecules.