Theoretical Study Of Electrostatic Surface Trap For Poplar Cold Molecules And Its Electrostatic Lattices

Cold molecules have some important applications in high-resolution spectroscopy and precise measurement, study of cold chemical reaction and cold collision, interferometer of matter wave, and quantum computing and information possessing and so on, the study of generation and application of cold molecules has obtained fast development. In this thesis, firstly, the principle, experiment and recent progress on cooling and trapping of neutral molecules have been briefly reviewed. Secondly, we give the theoretical study for the new schemes of electrostatic surface trapping and electrostatic lattice. In final, our research work is summarized and the future investigation is briefly looked ahead.We propose a new scheme to realize electrostatic surface trap for cold poplar molecules on a substrate by a single charged circular wire on a substrate and a grounded metal plate. When the positive voltage is applied on the circular wire, there will be an electrostatic well on the substrate. If the cold molecules in the low-field-seeking state interact with the electric field, they will feel a dipole gradient force due to the first-order Stark effect, and then the molecules will be attracted to the minimum of the electric field. We use commercial finite element software to calculate the spatial distribution of the electrostatic field of our charged circular wire and the distribution of its corresponding Stark trapping potential for CO molecules, and study the relationship between the position of the trapping center and the geometric parameters. We also analyze the feasibility of the scheme from three aspects, and propose an effective loading way and perform Monte-Carlo simulation for the dynamics process. The important results obtained supply reliably theoretical base for the experiment study.We also propose a novel electrostatic surface-trapping scheme by using a single charged square wire on the surface of the insulating substrate. We study the relationship between the position of the trapping center and the geometric parameters, and calculated the corresponding electric field distribution and its Stark trapping potential for cold CO molecules. We extend our single square wire to two-dimensional array for forming 2D molecular lattice, and realize electrostatic microstructure surface trapping. We calculated spatial electric field distribution in the x and z direction through the trapping center and the corresponding well depth, and discussed the potential applications of such 2D electrostatic lattice scheme in thefields of integrated molecule optics and molecular chip, quantum optics, quantum computing and information processing, etc.