Quantum Control and Transport of a Bose-Einstein Condensate

I will discuss recent work in my group on many-body quantum control and transport. In our rubidium experiment, a single Bose-Einstein condensate is optically trapped in crossed TEM01 modes, and we achieve confinement in two dimensions that is comparable to an optical lattice, but with single-atom addressability and detection. These conditions should enable the experimental realization of a ``quantum tweezer'' for atoms, preparation of atomic number states, and controlled atomic entanglement. In our sodium experiment we focus on the study of many-body quantum transport. Our system consists of a BEC confined to a hybrid magnetic/optical trap.~ Transverse confinement is provided by a 2-D axially symmetric magnetic trap and the BEC is confined axially by two focused spots that are separated by a controlled distance, creating an optical box.~ The atoms are then released into an optical potential along the axial direction that is created by an array of far detuned laser spots.~ Each spot~ can be independently controlled both in position and power, with a spatial resolution of six microns.~ This potential can be combined with a standing wave that is aligned along the trap axis, enabling transport measurements in potentials that can range from periodic to disordered. Finally, I will discuss recent ideas on constructing an optical ``one-way'' barrier for atoms.~ I will show how this idea can be used for phase space compression and cooling, as an optical realization of Maxwell's demon.