Special Condensed Matter Theory Seminar

Cenke Xu
University of California, Berkeley

Tuesday, November 28, 2006 Note different date and time!
4:00 pm in SPL 38 Note different room!

Quantum phase transition, self-duality, boson liquid, and dimensional reduction in systems with one dimensional gauge symmetries

Abstract: Symmetry and Dimensionality determine most of the universal properties of physical systems. In several special systems, the symmetry is larger than global symmetry, but smaller than local gauge symmetry. In these systems, the dimensionality is effectively reduced in various ways. The example systems are Josephson lattice of p+ip superconductors, and strongly correlated multiflavor bosonic atoms trapped in optical lattice. In the former system, an effective Ising variable was introduced to describe the time-reversal broken phases. Making use of exact self-duality of the model, a quantum phase transition between 1d bond ordered phase and disordered phase was studied. in the latter case, a novel stable bond-algebraic boson liquid phase is realized, in both 2 dimensional and 3 dimensional optical lattices. We will also briefly discuss our recent theoretical work on the the experiments on spin dimer material BaCuSiO, where a dimensional reduced critical point was reported.

Collaborators: Joel E. Moore, Matthew P. A. Fisher