Theoretical Study And Application Of Electrostatic Surface Bent Guiding For Cold Poplar Molecules

Over the last decades, atomic and molecular physics has come into a spectacular bloom, the newfashioned techniques to translationally cool (or slow down) gas atoms and molecules play unique roles in a number of diverse areas of fundamental interest. The study of slow atoms and molecules has led to uncharted territories ---- not just of atomic and molecular physics, but of physics at large. Cold molecules inspire many scientists. Ultracold atoms and cold atoms have many advantages in common, cold molecules and ultracold molecules in the near future, will further enhance the detection accuracy of basic research. Molecules have more freedom than atoms, molecules on the one hand increase difficulties in the process of the experimental controlling molecular; On the other hand, these complex molecules lay expansional fundation for precision measurement and quantum control. We compare the molecular and atomic, cold molecules can further develop many very interesting researches, what a pity, atoms does not own. Cold molecules reach a new height in basic research.In this paper, firstly, we review the basic theoretical knowledge of the ultra-cold molecules and cold molecules, the experimental generation and recent progress of cold molecules and ultra-cold molecules and their application. Secondly, we propose a novel scheme guiding cold polar molecules on the surface of a molecular chip by an electrostatic field generated by the combination of two parallel charged wires and sheets, and perform careful researches on our scheme to realize guiding for cold polar molecules. We also calculate the spatial distributions of the electric fields and their stark potential for ND3 molecules. Then we analyze the relationships between the electric field and the geometric parameters of two parallel charged sheet-wire system; we calculate and study the straight and bent guiding cold polar molecules by Monte-Carlo simulation. The transverse and longitudinal velocity distributions of the output guided molecular beam are simulated.We also generate cold molecules by stark velocity filter at room temperature. The buffer gas cooling technique is combined with the Stark velocity filter, obtaining a translationally and rotationally cold molecular (CH3F) beam. We measure the flux dependence and temperature of the filtered molecular beam on the guiding voltage, as well as on the reservoir pressure, and compare experimental results with simulation and that of other groups.Our study shows that we can use the proposed two parallel charged sheet-wire scheme to realize the manipulation and control of cold polar molecules in our surface guide on a chip and form special molecule elements, such as molecule storage ring and molecule velocity filter. The lowest attainable translational temperature of the cold molecules generated by buffer gas cooling combined with velocity filtering is about 1K, and their internal temperature is lower. The prospects and the future applications to studies of new physics and cold chemistry are presented, as well as future developments of researches on cold molecules in our lab. It lays foundation for trapping and storage of molecules and so on.