We study the superfluid-to-Mott insulator transition of bosons in a two-legged ladder optical lattice of a type accessible in current experiments on double-well optical lattices. The zero-temperature phase diagram is mapped out, with a focus on its dependence upon interchain hopping and the tilt between double wells. We find that the unit-filling Mott phase exhibits a nonmonotonic behavior as a function of the tilt parameter, producing a reentrant phase transition between the Mott insulator and superfluid phases.We study the superfluid-to-Mott insulator transition of bosons in a two-legged ladder optical lattice of a type accessible in current experiments on double-well optical lattices. The zero-temperature phase diagram is mapped out, with a focus on its dependence upon interchain hopping and the tilt between double wells. We find that the unit-filling Mott phase exhibits a nonmonotonic behavior as a function of the tilt parameter, producing a reentrant phase transition between the Mott insulator and superfluid phases.

Laser PhysicsMar 1, 20084 citations

Phases and Dynamics of Ultracold Bosons in a Tilted Optical Lattice

K. Sengupta

Quantum science and technologyJan 1, 20220 citations

Studies of Ultracold Bosons in Optical Lattices using Strong-Coupling Expansions

Manjari Gupta

Jun 14, 20180 citations

Novel Quantum Phases of Ultracold Bosonic Atoms in Honeycomb Optical Lattice

Qing-Qing Lu, Jing-Min Hou

We study the quantum phase transition of ultracold atoms in the honeycomb optical lattice. The Hamiltonian of ultracold bosonic atoms in the honeycomb optical lattice is derived. We take the mean-field approximation and further solve the Hamiltonian with the numerical diagonalization method. We obtain the phase diagram and find that the Mott-insulator (MI), density wave (DW) and modulated superfluid (MS) phases appear. Furthermore, the phase diagram is analyzed according to the order parameter and the average number of particles.We study the quantum phase transition of ultracold atoms in the honeycomb optical lattice. The Hamiltonian of ultracold bosonic atoms in the honeycomb optical lattice is derived. We take the mean-field approximation and further solve the Hamiltonian with the numerical diagonalization method. We obtain the phase diagram and find that the Mott-insulator (MI), density wave (DW) and modulated superfluid (MS) phases appear. Furthermore, the phase diagram is analyzed according to the order parameter and the average number of particles.

Communications in Theoretical PhysicsMay 1, 20103 citations

Magnetic phases of two-component ultracold bosons in an optical lattice

Andreas Hubener, Michiel Snoek, Walter Hofstetter

We investigate spin-order of ultracold bosons in an optical lattice by means of dynamical mean-field theory. A rich phase diagram with anisotropic magnetic order is found, both for the ground state and at finite temperatures. Within the Mott insulator, a ferromagnetic to antiferromagnetic transition can be tuned using a spin-dependent optical lattice. In addition we find a supersolid phase, in which superfluidity coexists with antiferromagnetic spin order. We present detailed phase diagrams at finite temperature for the experimentally realized heteronuclear $^{87}\text{R}\text{b-}^{41}\text{K}$ mixture in a three-dimensional optical lattice.We investigate spin-order of ultracold bosons in an optical lattice by means of dynamical mean-field theory. A rich phase diagram with anisotropic magnetic order is found, both for the ground state and at finite temperatures. Within the Mott insulator, a ferromagnetic to antiferromagnetic transition can be tuned using a spin-dependent optical lattice. In addition we find a supersolid phase, in which superfluidity coexists with antiferromagnetic spin order. We present detailed phase diagrams at finite temperature for the experimentally realized heteronuclear $^{87}\text{R}\text{b-}^{41}\text{K}$ mixture in a three-dimensional optical lattice.

arXiv:0902.2212Physical Review BDec 11, 2009110 citations

^{87}\text{R}\text{b-}^{41}\text{K}

mixture in a three-dimensional optical lattice.