Electronic structure and transport behaviours in some low-dimensional systems : Quantum Many-body and ab-initio studies

Abstract

When one or more of the dimensions of solid are reduced sufficiently in size, its property departs significantly from that of the bulk state. With this type of reduction in size, many exotic phenomena emerge. The resulting structure is a low-dimensional system. The typical dimensions are usually in the range of few nanometers. One of the most direct effects of reducing the size of materials to the nanometer range is the appearance of quantization effects due to the confinement of the movement of electrons. The study of low-dimensional quantum phenomenon has led to entirely new fields of research. Low-dimensional systems have shed new light on the difficult questions of how disorder and electron-electron interaction affect quantum system. When the size of the system achieves the electron wave length, the role of Quantum Mechanics is crucial. Thus low-dimensional systems exhibit quantum effects such as Aharonov-Bohm effect, persistent currents, phase-coherent transport and Luttinger liquid. The theory of nanostructures is an intellectually very rewarding topic.