Physics & Astronomy Colloquium
3:30 PM, Friday, October 30, 2009
Room 155, Chem-Phys Building
Dr. Cheng Chin
James Franck Institute and Department of Physics
University of Chicago
"-Having the cake and seeing it too
In Situ Observation of Incompressible Mott Insulating Domains in Ultracold Gases''
Bose-Hubbard model describes one of the simplest realizations
of a quantum phase transition, a phase transition that occurs
even at zero temperature. Near the phase boundary (critical point),
resembling that of Ising-type magnetics in higher dimensions,
is expected to emerge with a full universal behavior.
In particular, fluctuations and
correlations are expected at all length scales.
Our observation of atomic density profiles in optical lattices
provides a powerful tool to determine all relevant thermo-dynamical
quantities, as well as density fluctuations and density-density
correlations. I will describe our efforts to identify the superfluid-Mott
insulator phase boundary, to extract quantum fluctuations and
correlations, and also discuss the prospects to identify and
characterize quantum criticality and universality based on
trapped quantum gases in an optical lattice.
 Quantum phase transition from a superfluid to a Mott insulator in a gas of ultracold
atoms, M. Greiner, O. Mandel, T. Esslinger, T. W. Haensch, and I. Bloch, Nature 415, 39-44
 In situ observation of incompressible Mott-insulating domains in ultracold atomic gases,
N. Gemelke, X. Zhang, C.-L. Hung, and C. Chin, Nature 460, 995-998 (2009).
Refreshments will be served in CP 179 at 3:15 PM