Single-electron phenomena in semiconductors

The study of single-electron phenomena associated with tunnelling in semiconductor nanostructures has emerged in recent years as a major forefront of condensed matter physics, whose implications range from fundamental physics to electronic device applications. This paper presents a tutorial review of the subject, with emphasis on the role of single-electron charging in such semiconductor 'quantum dots'. The main purpose is to describe the various phenomena observed in these experiments and to present the theoretical understanding of these phenomena in an introductory fashion. The paper attempts to explain the underlying physics at the intuitive level and tries to draw, as much as possible, a unifying perspective on a relatively large body of knowledge acquired within a short time by the conjunction of many individual contributions.