MESOSCOPIC PHYSICS, ITS APPLICATION AND USES

ABSTRACT

An ongoing tendency in modern material science is to purpose and to instigate systems containing smaller and smaller structures. The resulting systems approach the mesoscopic regime in which the quantum phase coherence leads to important corrections to the electronic properties of the devices. At the same time, microscopic details of the sample, like the exact impurity configuration in disordered systems, determine some quantitative features of the behavior. This can lead to pronounced fluctuations of a quantity measured in different samples which are macroscopically equivalent. This aim of this series of lectures is to introduce the mesoscopic regime and to review a selection of the most important effects appearing in mesoscopic system. The theory of electronic transport in mesoscopic samples is illustrated in the framework of the Landauer in which the conductance is determined by the scattering properties of the sample. As an example for the importance of electron-elelctron interactions for the conductance, we describe the coulomb blockade effect appearing in devices containing ultra-small tunnel junctions or quantum dots. The importance of mesoscopic effects for basic research, as well as for applications in nanoelctronic devices and for metrology, is stressed.