The orbital degree of freedom plays a fundamental role in understanding the unconventional
properties in solid state materials. Experimental progress in quantum atomic gases has …

In this work, we consider the dynamics of bosons in bands with nontrivial topological
structure. In particular, we focus on the case where bosons are prepared in a higher-energy …

The system of a cold atomic gas in an optical lattice is governed by two factors: nonlinearity
originating from the interparticle interaction, and the periodicity of the system set by the …

In this paper we show that for sufficiently strong atomic interactions, there exist analytical
solutions of current-carrying nonlinear Bloch states at the Brillouin zone edge to the model of …

We study experimentally the stability of excited, interacting states of bosons in a double-well
optical lattice in regimes where the nonlinear interactions are expected to induce …

We study theoretically the superfluidity and stability of a Bose-Einstein condensate (BEC)
whose interatomic scattering length is periodically modulated with optical Feshbach …

Band structure is an important tool to characterize the physical properties of periodic
systems. In this work, we investigate the nonlinear spectrum and current density in cold …

We investigate p-orbital Bose-Einstein condensates in both the square and checkerboard
lattice by numerically solving the Gross-Pitaevskii equation. The periodic potential for the …

A bstract The instability of superfluids in optical lattice has been investigated using the
holographic model. The static and steady flow solutions are numerically obtained from the …

The Bloch states of Bose-Einstein condensates (BECs) in pure nonlinear lattices (NLs) are
dynamically unstable so that they cannot show superfluidity. We overcome this problem by …