| Bose-Fermi degenerate quantum gases are the systems which have excellent properties and a high degree of manipulation and controllability. Therefore, the quantum gases have become a very popular research branch in the cold atomic physics realm. The study about the gases not only needs to consider different quantum statistical properties for Bosonic and Fermionic atoms, but also needs to take into account the relationship of intra-atoms interaction. In order to experimentally research the quantum gases, we must firstly prepare these gases in the lab. Secondly, we should have extensive means to detect and control these atoms. During my doctorial study period, the main work is to build an experimental layout on which we could study Bose-Fermi quantum gases. This thesis had described some of results achieved in experiments. The results include decelerating the 6Li atoms by a 2D-MOT apparatus, magneto-optical trapping for 87Rb,40K,6Li atoms, transferring 87Rb atoms from a high pressure chamber into a low pressure chamber, continuously cooling 87Rb atoms in an ultra-high vacuum glass cell and detecting the atomic properties by time-of-flight images. The detailed operating parameters have given in thesis. And We carefully investigate the influence for 40K MOT by the side-bands of tapered amplifier and multi-chromatic frequency laser improving the loading efficiency of 6Li MOT.The main results were given as follows:1. We have established a compact Bose-Fermi gases experimental setup. It consists of three departments. A 2D-MOT apparatus primarily decelerate 6Li atoms. A MOT chamber is used to achieve Magneto-Optical Trap of 87Rb,40K, 6Li atoms. An ultrahigh vacuum chamber is used to create Bose-Fermi quantum gases. The ultrahigh vacuum chamber has a vacuum up to 1.6×10-9 Pa. In this chamber, we will also study quantum physical phenomena of Bose-Fermi quantum gas.2. We have made a lithium atomic cell for saturated absorption spectrum, and successfully locked 671 nm semiconductor lasers. The cell vacuum chamber was constructed by stainless steel in which an enriched 6Li atom lithium sam-ple was placed. Using commercial rubidium atomic cell and potassium atomic cell, we respectively locked 780 nm and 767 nm semiconductor lasers. From the chamber background, we have realized a Magneto-Optical Trap of 87Rb atoms by capturing the laser cooled atoms. With homemade potassium atomic dis-penser, we captured and trapped 40K atoms. We firstly slowed the hot 6Li atoms by a 2D-MOT layout. Then, assisting by laser pushing atoms method, a 6Li Magneto-Optical Trap was loaded.3. Due to the nonlinear effect of tapered amplifier crystal, when a laser with two frequencies was injected into the amplifier, the output light might have sidebands. We have carefully analysed the loading atomic number of 40K atom Magneto-Optical Trap, which was affected by the sidebands of cooling and re-pumping light. We have expanded the spectrum of the cooling light by an EOM. And the spectral interval compared with natural linewidth was used in 2D-MOT configuration. The loading rate to Magneto-Optical Trap of 6Li atoms has im-proved by four times.4. With a pushing laser, we transferred 87Rb atoms to the ultra-high vacuum chamber (Glass Cell). And the 87Rb atoms was firstly imprisoned in a Magneto-Optical Trap of other chamber. When captured enough atoms in Glass Cell, a compressed MOT (CMOT) has been used to enhance the spatial density of trapped 87Rb atoms. We have measured the loading time and the life time of 87Rb atoms in Magneto-Optical Trap by collecting fluorescence. Otherwise, using the absorption imaging (TOF) method, we have measured the number, temperature and spatial density of atoms trapped in Magneto-Optical Trap and compressed MOT. Finely, we have directly loaded the atoms to a quadruple magnetic trap after the compressed MOT process in which preliminary experimental results have been obtained. |
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