Cold Neutral Atoms in Optical Lattices.

Abstract

In this thesis, I study the properties of cold neutral atoms, including Bose-Einstein condensates (BEC), inside periodic light-shift potentials created by optical lattices. In the first part, a new optical-lattice scheme, employing Raman transitions, hereafter referred to as a Raman Optical Lattice (ROL), is investigated. This optical lattice possesses a novel sub-Doppler cooling mechanism and a reduced periodicity. Both theoretical and experimental results con¯rm these two characteristics of the ROL. In the second half of the thesis, instead of thermal atoms, optical lattices are loaded with condensate atoms. Our BEC apparatus and the procedure towards forming a BEC are described in detail. After the achievement of the BEC, a 1D far-detuned optical lattice is applied to the BEC. A number of phenomena are observed, including Kapitza-Dirac diffraction, thermal atom interference, atom interferometry, Bloch oscillations, and a superfluid to Mott-insulator transition. Finally a brief discussion about future work is given.