Seminar
Tuesday, 08 November, 2011
Group Seminar LMU: The Superfluid to Mott Glass Transition for Random Bosons in Two Dimensions: a Real Space RG Perspective
Tuesday, 08.11.2011 10:00 a.m. (s.t.) in H107, Fakultät für Physik LMU
David Pekker, Caltech Condensed Matter Theory Group
We study the zero temperature superfluid-insulator transition for a two-dimensional model of interacting lattice bosons in the presence of quenched disorder and particle-hole symmetry. Our approach is to extend the strong disorder renormalization group of Altman, Kafri, Polkovnikov, and Refael from one to two spatial dimensions. We find an unstable, finite disorder fixed point that governs the transition between the superfluid and a gapless, glassy insulator. We present evidence that this glassy phase is the incompressible Mott glass and that the transition from this phase to the superfluid is driven by a percolation-like process. Finally, we provide estimates of the critical exponents governing this transition.