Institute for Quantum Information and Matter Seminar

Monday July 9, 2012 4:00 PM

Topological flat bands from dipolar systems

Speaker: Norman Yao, Harvard University
Location: East Bridge 114
Topological flat bands provide a fascinating route to the realization of novel strongly correlated phenomena. In this talk, I will describe and analyze a physical system that naturally admits nearly flat bands with non-zero Chern index. Our approach utilizes a two-dimensional array of three-level dipoles driven by inhomogeneous electromagnetic fields. I will demonstrate that dipolar interactions can generate arbitrary uniform background gauge fields for an effective collection of conserved hardcore bosons, namely, the dressed spin-flips. These gauge fields result in topological band structures, whose bandgap can be significantly larger than the corresponding bandwidth. To probe the many-body properties of this system, we perform exact diagonalization of the full interacting Hamiltonian at half-filling and uncover superfluid, crystalline, supersolid and fractional quantum Hall phases. An experimental realization using either spins in the solid-state or ultra-cold polar molecules is considered. Joint work with: C. Laumann, A. V. Gorshkov, S. D. Bennett, E. Demler, P. Zoller, M. Lukin
Series Condensed Matter Physics Seminar Series

Contact: Ann Harvey at 4964 aharvey@caltech.edu