Related papers: Dipolar Molecules in Optical Lattices
We study quantum phases of ultracold bosonic atoms in a two-dimensional optical superlattice. The extended Bose-Hubbard model derived from the system of ultracold bosonic atoms in an optical superlattice is solved numerically with…
The extended Bose-Hubbard model subjected to a disordered potential is predicted to display a rich phase diagram. In the case of uniform random disorder one finds two insulating quantum phases -- the Mott-insulator and the Haldane insulator…
Ultracold Bose gases in one-dimensional optical lattices constitute an important benchmark problem in the study of strongly interacting many-body quantum phases. Here we present a combined experimental and theoretical study of their…
We investigate the quantum phases of hard-core dipolar bosons confined to a square lattice in a bilayer geometry. Using exact theoretical techniques, we discuss the many-body effects resulting from pairing of particles across layers at…
We present a concise review of the physics of ultra-cold dipolar gases, based mainly on the theoretical developments in our own group. First, we discuss shortly weakly interacting ultra-cold trapped dipolar gases. Dipolar Bose-Einstein…
The one dimensional Bose-Hubbard model at a unit filling factor is studied by means of a very high order symbolic perturbative expansion. Analytical expressions are derived for the ground state quantities such as energy per site, variance…
We discuss the superfluid to Mott-insulator transition of cold atoms in optical lattices recently observed by Greiner et.al. (Nature 415, 39 (2002)). The fundamental properties of both phases and their experimental signatures are discussed…
We consider the transfer of a two-species Bose-Einstein condensate into an optical lattice with a density such that that a Mott-insulator state with one atom per species per lattice site is obtained in the deep lattice regime. Depending on…
Extended Bose Hubbard models with nearest neighbour interaction describe minimally the effect of long range interaction on ultra cold atoms in deep optical lattices. Rotation of such optical lattices subject such neutral cold atoms to the…
The Bose-Hubbard model of a two-fold degenerate Bose gas is studied in an optical lattice with one particle per site and virtual tunneling to empty and doubly-occupied sites. An effective Hamiltonian for this system is derived within a…
We show anisotropy of the dipole interaction between magnetic atoms or polar molecules can stabilize new quantum phases in an optical lattice. Using a well controlled numerical method based on the tensor network algorithm, we calculate…
We discuss the superfluid to Mott insulator transition of an atomic Bose gas in an optical lattice with high filling factors. We show that also in this multi-band situation, the long-wavelength physics is described by a single-band…
Spectral properties of the two-dimensional Bose-Hubbard model, which emulates ultracold gases of atoms confined in optical lattices, are investigated by means of the variational cluster approach. The phase boundary of the quantum phase…
When particles move through a crystal or optical lattice, their motion can sometimes become frozen by strong external forces -- yet collective motion may still emerge through subtle many-body effects. In this work, we explore such…
We consider a mixture of hard core bosonic polar molecules, interacting via repulsive dipole-dipole interaction, and one atomic bosonic species. The mixture is confined on a two-dimensional square lattice and, at low enough temperatures,…
The phase diagram of ultracold bosons in realistic optical superlattices is addressed via second-order {\it cell} strong coupling perturbative expansions for the Bose-Hubbard model describing the system. Taking advantage of the cell…
Ultra-cold atoms in optical lattices realize simple, fundamental models in condensed matter physics. Our 87Rb Bose-Einstein condensate is confined in a harmonic trapping potential to which we add an optical lattice potential. Here we…
We investigate the emergence of a myriad of phases in the strong coupling regime of the dipolar Hubbard model in two dimensions. By using a combination of numerically unbiased methods in finite systems with analytical perturbative…
We consider phase coherence collapse and revival in deep optical lattices, and calculate within the Bose-Hubbard model the revival amplitude damping incurred by a finite tunneling coupling of the lattice wells (after sweeping from the…
We investigate the physics of dipolar bosons in a two dimensional optical lattice. It is known that due to the long-range character of dipole-dipole interaction, the ground state phase diagram of a gas of dipolar bosons in an optical…