Experiment Study Of Ultracold Rubidium And Cesium Atoms About Collision Characteristics

The cold atoms in Magneto-Optical trap has many advantages, such as little effect by the environment, low velocity, high density. They have become the very important research object in the atomic and molecular physics. And they have been used in ultralow temperature physics, ultralow energy collision physics, atomic high resolution spectroscopy, nonlinear optics of atom material waves and so on. The cold collisions are an important research field in atomic and molecular physics. They can be used to get the information about the atom and molecular. And the research is very important for weakly interacting atoms, matter-wave coherences and optical manipulation of inelastic and reactive processes.We realize the simultaneous cooling and trapping the two species atom in double MOT. We measure the collision loss rate of one species atoms in single MOT, and the collision loss rate of two species atoms in double MOT. Then we explain the result by the theory of Gallagher—Prichard model.We review the cooling and trapping the atoms in this thesis, and we introduce the research status and significance of heteronuclear cold collisions. In the theory, we analyze the two-body collision mechanism, and we explain the result by the Gallagher—Prichard model. In the experiment, we introduce the vacuum system and the optical system, and we obtain the heteronuclear cold collision rate of rubidium and cesium in double MOT.The main works of the thesis is as follows: 1,The diode laser's frequency is stabilized by the saturated absorptionspectroscopy in the experiment 2,Rubidium and cesium are simultaneous cooling and trapping in double MOT, and the atomic cloud of two species atoms are superposition. The number and the size of atomic cloud are measured in the experiment. 3,The trap loss rate of homonuclear cold collisions and heteronuclear cold collisions are obtained. The result is explained by the Gallagher-Pritchard model.