Disordered Bose-Einstein condensates in quasi-one-dimensional magnetic microtraps.
We analyze the effects of a random magnetic potential in a microfabricated waveguide for ultracold atoms. We find that the shape and position fluctuations of a current carrying wire induce a strong Gaussian correlated random potential with a length scale set by the atom-wire separation. The theory is used to explain quantitatively the observed fragmentation of the Bose-Einstein condensates in atomic waveguides. Furthermore, we show that nonlinear dynamics can be used to provide important insights into the nature of the strongly fragmented condensates. We argue that a quantum phase transition from the superfluid to the insulating Bose glass phase may be reached and detected under the realistic experimental conditions.
Physics Department, Harvard University, Cambridge, MA 02138, USA.
Daw-Wei
DW
Wang
Mikhail D
MD
Lukin
Eugene
E
Demler