Related papers: Dirac Point Structure in a Bose-Einstein Condensat…
We calculate the dynamics of the one and two body correlation functions in a homogeneous Bose gas at zero temperature following a sudden change in the interaction strength, with and without an underlying lattice. We focus on conceptually…
For bosons with flat energy dispersion, condensation can occur in different symmetry sectors. Here, we consider bosons in a Kagome lattice with $\pi$-flux hopping, which in the presence of mean-field interactions exhibit degenerate…
The honeycomb lattice possesses a novel energy band structure, which is characterized by two distinct Dirac points in the Brillouin zone, dominating most of the physical properties of the honeycomb structure materials. However, up till now,…
A weakly interacting Bose gas on a simple cubic lattice is considered. We prove the existence of the standard or zero-mode Bose condensation at sufficiently low temperature. This result is valid for sufficiently small interaction potential…
We study the statics and dynamics of anisotropic, stable, bright and dark-in-bright dipolar quasi-two-dimensional Bose-Einstein condensate (BEC) solitons on a one-dimensional (1D) optical-lattice (OL) potential. These solitons mobile in a…
By numerical simulation and variational analysis of the Gross-Pitaevskii equation we study the localization, with an exponential tail, of a dipolar Bose-Einstein condensate (DBEC) of $^{52}$Cr atoms in a three-dimensional bichromatic…
We investigate the interaction-driven instability of a quadratic band crossing arising for ultracold bosonic atoms loaded into a two-dimensional optical lattice. We consider the case when the degenerate point becomes a local minimum of both…
We present the theoretical and mathematical foundations of stability analysis for a Bose-Einstein condensate (BEC) at Dirac points of a honeycomb optical lattice. The combination of s-wave scattering for bosons and lattice interaction…
The Bloch and dipole oscillations of a Bose Einstein condensate (BEC) in an optical superlattice is investigated. We show that the effective mass increases in an optical superlattice, which leads to localization of the BEC, in accordance…
Extending recent work to finite temperatures, we calculate the Landau damping of a Bogoliubov excitation in an optical lattice, due to coupling to a thermal cloud of such excitations. For simplicity, we consider a 1D Bose-Hubbard model and…
Recent experimental data on Bose-Einstein Condensation (BEC) of magnons in the spin-gap compound Yb$_2$Si$_2$O$_7$ revealed an asymmetric BEC dome arXiv:1810.13096v2. We examine modifications to the Heisenberg model on a breathing honeycomb…
We investigate the low-lying excitations of a stack of weakly-coupled two-dimensional Bose-Einstein condensates that is formed by a one-dimensional optical lattice. In particular, we calculate the dispersion relations of the monopole and…
We discuss localized ground states of Bose-Einstein condensates in optical lattices with attractive and repulsive three-body interactions in the framework of a quintic nonlinear Schr\"odinger equation which extends the Gross-Pitaevskii…
We discuss several possible experimental signatures of the Bose-Einstein condensation (BEC) transition for an ultracold Bose gas in an inhomogeneous optical lattice. Based on the commonly used time-of-flight imaging technique, we show that…
We study the propagation of sound waves in a Bose-Einstein condensate trapped in a one-dimensional optical lattice. We find that the velocity of propagation of sound wavepackets decreases with increasing optical lattice depth, as predicted…
This article provides a synopsis of our recent experimental work exploring Bose-Einstein condensation in metastable higher Bloch bands of optical lattices. Bipartite lattice geometries have allowed us to implement appropriate band…
We study the area-dependent entropy and two-site entanglement for two state Bose-Einstein condensates in a 2D optical lattice. We consider the case where the array of two component condensates behave like an ensemble of spin-half particles…
We show that Bose-Einstein condensates in optical lattices with broken time-reversal symmetry can support chiral edge modes originating from nontrivial bulk excitation band topology. To be specific, we analyze a Bose-Hubbard extension of…
We study Bogoliubov excitations of a spinor Bose Einstein condensate in a honeycomb periodic potential, in the presence of a Zeeman field and of a spin-orbit coupling specific for photonic systems, which is due to the energy splitting…
We reveal underlying principles of nonlinear localization of a two-component Bose-Einstein condensate loaded into a one-dimensional optical lattice. Our theory shows that spin-dependent optical lattices can be used to manipulate both the…