Research on the Theory of Landau-Zener Problems
|School||Sichuan Normal University|
|Keywords||Landau-Zener Tunneling Time evolution operator Tunneling probability Two-level system Spin - boson model Dissipative system|
Energy level Landau-Zener tunneling is a basic and important quantum phenomenon , it exists and there is a wide range of applications in various physical systems . In this thesis, a variety of two-level systems , the Landau-Zener tunneling probability theory and methods of computation , and focuses on the time evolution operator method , and this method is accurate to solve all kinds of closed complex two-level system of tunnel wear a chance . Paper is divided into five chapters , of which the third chapter of the time evolution operator method is accurate for solving the two-level system , the tunneling probability for my work , the full text of the specific content is organized as follows : The first chapter briefly describes the Landau-Zener tunneling phenomena research background, current situation and the practical significance of the study . The second chapter describes what Landau-Zener tunneling study the tunnel wearing the specific model of the phenomenon , while recalling physicist Zener initial description of this tunnel phenomenon : the original Zener tunneling model . Finally, a two-level system driven cycle field tunneling model . Chapter III , we present the time evolution operator method and accurate solving the ideal two-level system tunneling probability , the use of graphics and intuitive analysis of each system tunneling probability relationship changes over time , by comparison with other methods and fully reflects the simplicity and feasibility of this approach . Chapter brief dissipative tunneling model and the tunneling probability of the two-level system . Chapter V summarizes the specific content of this study , and gives a brief introduction to the work and ideas of our next step .