Flat band in two-dimensional non-Hermitian optical lattices

Flat Chern band in a two-dimensional organometallic framework.

By combining exotic band dispersion with nontrivial band topology, an interesting type of band structure, namely, the flat Chern band, has recently been proposed to spawn high-temperature fractional quantum Hall states. Despite the proposal of several theoretical lattice models, however, it remains doubtful whether such a "romance of flatland" could exist in a real material. Here, we present a ...

Global Photonic Band Gaps in Two-Dimensional Metallic Lattices

The fundamental and higher frequency global photonic band gaps are obtained for transverse electric (TE) and transverse magnetic (TM) modes in photonic band gap (PBG) structures consisting of two-dimensional (2D) square and triangular lattices of perfectly conducting cylinders. The global photonic band gaps in metallic lattice, which are found to differ qualitatively as well as quantitatively f...

Photonic band structure of two-dimensional atomic lattices

Controlled transport of matter waves in two-dimensional optical lattices.

We propose a method for achieving dynamically controllable transport of highly mobile matter-wave solitons in a driven two-dimensional optical lattice. Our numerical analysis based on the mean-field model and the theory based on the time-averaging approach demonstrate that a fast time-periodic rocking of the two-dimensional optical lattice enables efficient stabilization and manipulation of spa...

Bloch oscillations of cold atoms in two-dimensional optical lattices

Bloch oscillations of cold atoms in two-dimensional optical lattices are studied. The cases of separable and nonseparable potentials are compared by simulating the wave-packet dynamics. For these two classes of optical potential, the Bloch oscillations were found to be qualitatively the same in the case of a weak static field but fundamentally different in the case of a strong field. In additio...