Quantum Chain And Its Array System Electronic Transport Properties

No more than 30 years since the 1980s', mesoscopic physics, one burgeoning subject of Condensed States Physics, quickly comes into being and becomes a new hotspot of the studies in Condensed States Physics. In recent several years, progress in nanofabrication of quantum devices has allowed one to study the electron transport through quantum dots (QD's) in a very controllable way. QD's are very promising systems due to their physical properties as well as their potential applications in electronic devices. In this thesis, we study the electronic transport properties through quasi-one dimensional quantum systems. The aim is to explore the physical mechanisms of the found new effect in these systems, and to supply physical models and theoretical validity in designing novel quantum devices with better properties.The thesis is divided into four chapters, which are described as follows. In chapter one ,we introduce the structures and characteristics in mesoscopic physics as well as several numerical methods to calculate the conductor such as the mode-matching method, the transfer-matrix method and the scatter-matrix method.In chapter two, the lattice Green's function is illustrated, especially recursive Green's function method. Comparing with other theoretical methods, the recursive Green's function method can be applied conveniently to study the varied nano-fabrication of quantum devices and can effectively resolve big-scale systems by dividing them into several parts.In chapter three, properties of electronic transport in the'T-model'mesoscopic device formed by the main quantum wire with one or two side quantum-dot chain are investigated by using a recursive Green's function technique. At first, transports through the sidelong quantum-wire with one side-coupled quantum dot arrays are investigated by using a recursive Green's function technique based on some characteristics of one dimensional two-terminal system. We get the transport pictures with some varied parameters. In addition, the sidelong quantum-wire with two side-coupled quantum dot arrays are also investigated by using a recursive Green's function technique. Two side-coupled quantum dot arrays can be connected to the same lattice dot or tow lattice dots which are in the sidelong quantum-wire. H-typed quantum wire has been particularly analyzed.In chapter four, transports through the quantum wire with periodic side-coupled quantum dot arrays are investigated by using a recursive Green's function technique. The side-coupled quantum dot arrays can be finite quantum-dot chain or infinite quantum-dot chain.The last chapter presents a conclusion of this thesis and some prospects for this investigation. Keywords: recursive Green's function, infinite quantum-dot chain, finite quantum-dot chain, electron transport...