The post-graphene era: strongly interacting Dirac fermions with cold atoms
KTH/Nordita/SU seminar in Theoretical Physics [before December 2013]
Wednesday 26 August 2009
to 12:00 at
Cristiane Morais Smith (University of Utrecht)
Uniform magnetic fields are ubiquitous in nature, but this is not the case for staggered magnetic fields. I will discuss an experimental set-up recently proposed by us , which may allow for the realization of a "staggered magnetic field" in a 2D optical lattice loaded with cold atoms. If the lattice is loaded with
bosons, the effective Hamiltonian of the system is a Bose-Hubbard one,
with complex and anisotropic hopping coefficients. A very rich phase
diagram emerges from the model: besides the usual Mott-insulator and
zero-momentum condensate, a new phase with a finite momentum condensate
becomes the ground-state at high-rotation . An extension for
fermionic atoms leads to an anisotropic Dirac spectrum, which is relevant
to graphene and high-Tc superconductors . When the system is loaded
with a mixture of fermions and bosons, an unconventional superconducting phase may be realized .
 A. Hemmerich and C. Morais Smith, Phys. Rev. Lett. 99,
 Lih-King Lim, A. Hemmerich, and C. Morais Smith, Phys.
100, 130402 (2008).
 Lih-King Lim, A. Lazarides, A. Hemmerich, and C. Morais