Manipulation Of Quantum Degenerate ⁴⁰K-⁸⁷Rb Fermi-Bose Mixtures In Magnetic And Optical Trap

This thesis firstly presents experiments in quantum degenerate fermionic 40K and bosonic 87Rb atoms. Then we achieve 87Rb Bose-Einstein condensation (BEC) with microwave (MW) evaporation and perform transport of 87Rb Bose-Einstein condensate in QUIC trap. We also construct a Far-Off Resonance optical dipole trap (FORT) and create Bose-Einstein condensation in it.Degenerate 40K Fermi gases have been produced by sympathetic cooling with bosonic 87Rb. Some experimental principle and methods are firstly described, such as laser cooling, evaporative cooling, absorption imaging and so on. And then experimental apparatus based on double magneto-optical trap are demonstrated. In this part, more details focus to the performance of instruments and circuits, for instance, running modes of CCD and the working of currents controlling circuits for quadruple-Ioffe configuration coils. After that, the experimental methods and steps to approach quantum degeneration are listed and described in detail. Here the debugging and optimizing of experimental system are discussed.After the achievement of quantum degeneration of Bose-Fermi mixture, our experimental system is extended. With it, several experiments are realized, including the realization of BEC with MW evaporation, transport of BEC, separation of spin states of 87Rb BEC, and the creation of BEC in an optical trap. For the atomic transport, we directly observe the locomotion track of atoms under two conditions with or without a levitational magnetic field. We have transported atoms into the geometric center of glass cell with a levitating magnetic field from the initial position in a QUIC trap, which will be useful for a better optical access in our later experiments. And during the transport of atoms without a levitational magnetic field, we realize a larger separation of different spin ground states of 87Rb in space. For MW evaporation experiment, we successfully obtain BEC although with some atoms in wrong Zeeman substate, and explain the phenomena by comparing principles of MW radiation evaporation with radio frequency induced evaporation. Then a FORT composed of two 1064 nm lasers is used to trap atoms and 87Rb BEC is created by lowering the optical dipole trap depth. This will provide us with the starting point for studies of the properties of BFM in an optical lattice.