相关论文: Identifying the Bose glass phase
We investigate the behavior of the quasi-particle energy gap near quantum phase transitions in a two-dimensional disordered boson Hubbard model at a commensurate filling. Via Monte Carlo simulations of ensembles with fixed numbers of…
Using a strong disorder real-space renormalization group (RG), we study the phase diagram of a fully disordered chain of interacting bosons. Since this approach does not suffer from run-away flows, it allows a direct study of the insulating…
In a one-dimensional shallow optical lattice, in the presence of both cubic and quintic nonlinearity, a superfluid density wave is identified in a Bose-Einstein condensate. Interestingly, it ceases to exist when only one of these…
We study a one-dimensional disordered Bose fluid using bosonization, the replica method and a nonperturbative functional renormalization-group approach. The Bose-glass phase is described by a fully attractive strong-disorder fixed point…
A spin-wave approach of the zero temperature superfluid-insulator transition for two-dimensional hard-core bosons in a random potential $\mu=\pm$ W is developed. While at the classical level there is no intervening phase between the…
The quantum phase transition point between the insulator and the superfluid phase at unit filling factor of the infinite one-dimensional Bose-Hubbard model is numerically computed with a high accuracy, better than current state of the art…
We determine the phase diagram of a one-dimensional Bose gas in the presence of disorder with short- and long-range correlations, the latter decaying with distance as $1/|x|^{1+\sigma}$. When $\sigma<0$, the Berezinskii-Kosterlitz-Thouless…
We investigate the zero temperature phase diagram of a gas of bosonic atoms in one- and two-color standing-wave lattices in the framework of the Bose-Hubbard model. We first introduce some relevant physical quantities; superfluid fraction,…
The effect of nearest-neighbor repulsion on the ground-state phase diagrams of three-body constrained attractive Bose lattice gases is explored numerically. When the repulsion is turned on, in addition to the uniform Mott insulating state…
We study the quantum phase transition from the superfluid to the Mott insulator state in two and three dimensional Bose-Einstein condensate (BEC) with optical lattices using Bose-Hubbard Hamiltonian within the Generalized…
We use quantum Monte Carlo simulations to study the phase diagram of hard-core bosons with short-ranged {\it attractive} interactions, in the presence of uniform diagonal disorder. It is shown that moderate disorder stabilizes a glassy…
Bosons in a periodic lattice with on-site disorder at low but non-zero temperature are considered within a mean-field theory. The criteria used for the definition of the superfluid, Mott insulator and Bose glass are analysed. Since the…
We study the effect of commensurability (integer filling factor) on the superfluid (SF) - Bose-glass (BG) transition in a one-dimensional disordered system in the limit of weak disorder, when the effect is most pronounced and, on the other…
We report on results of Quantum Monte Carlo simulations for bosons in a two dimensional quasi-periodic optical lattice. We study the ground state phase diagram at unity filling and confirm the existence of three phases: superfluid, Mott…
The Bose glass (BG) phase is the Griffiths region of the disordered Bose Hubbard model (BHM), characterized by finite, quasi-superfluid clusters within a Mott insulating background. We propose to utilize this characterization to identify…
We study superfluid to Anderson insulator transition of strongly repulsive Bose gas in a one dimensional incommensurate optical lattice. In the hard core limit, the Bose-Fermi mapping allows us to deal with the system exactly by using 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 present a study of the superfluid properties of atomic Bose gases in optical lattice potentials using the Bose-Hubbard model. To do this, we use a microscopic definition of the superfluid fraction based on the response of the system to a…
We study the properties of the Bose glass phase of localized flux lines in irradiated superconductors near the matching field $B_{\Phi}$. Repulsive vortex interactions destroy the Mott insulator phase predicted to occur at $B=B_\Phi$. For…
We realize a single-band 2D Bose-Hubbard system with Rb atoms in an optical lattice and measure the condensate fraction as a function of lattice depth, crossing from the superfluid to the Mott-insulating phase. We quantitatively identify…