Ultrafast Electron Diffraction, Electron Gun Theory And Experimental Research

With the constantly development of science and technology, people are getting more and more interested in the microcosmic movement. As ultrafast electron diffraction (UED) has characteristic of high spatial resolution of 0.01nm and temporal resolution of femtosecond, it is widely used in ultra-fast diagnosis experiment. Ultrafast Electron Diffraction plays a significant role in study areas of crystallite, surface and film and the chemical reactions and the biologic reactions as a unique method for measuring matter structure and phase transitions,. Therefore, many scientists at home and abroad are engaged in this field, and have developed many ultrafast electron diffraction systems for scientific research study.In this thesis, an ultrafast electron diffraction system with high spatial resolution has been developed. Then with the feature of high spatial and temporal resolution, this system can make high time resolution shoot for dynamic atom and molecular.Firstly, set up optics system and parameters for ultrafast electron diffraction system according to experiments requirements. Those are 50Kv accelerating voltage, magnetism loop for electron beam focusing, deflector which is composed of flat and table-flap and double MCP for electron double increase in exploration system. Secondly, take Monte-Carlo simulation method, boundary element method and RK calculation to figure out electric field, magnetic field and electron track. Finally, get the designing parameters for ultrafast electron diffraction system.Based on the designed model and results, all components of the UED system such as photocathode, magnetic focusing and static electrical deflection system, electrical image intensify system, vacuum system and electrical circuit control system are developed. This ultrafast electron diffraction system can be definitely used in scientific experiment after system debugging as well as the parameter testing.