Hierarchical dimensional crossover of an optically-trapped quantum gas with disorder

Abstract

Dimensionality serves as an indispensable ingredient in any attempt to formulate the low-dimensional physics, and studying the dimensional crossover at a fundamental level is challenging. The purpose of this work is to study the hierarchical dimensional crossovers, namely the crossover from three dimensions (3D) to quasi-2D and then to 1D. Our system consists of a 3D Bose-Einstein condensate (BEC) trapped in an anisotropic 2D optical lattice characterized by the lattice depths $V_1$ along the $x$ direction and $V_2$ along the $y$ direction, respectively, where the hierarchical dimensional crossover is controlled via $V_1$ and $V_2$. We analytically derive the ground-state energy, quantum depletion and the superfluid density of the system. Our results demonstrate the 3D-quasi-2D-1D dimensional crossovers in the behavior of quantum fluctuations. Conditions for possible experimental realization of our scenario are also discussed.

6 pages, 3 figures

References in corpus (5)

• Many-Body Physics with Ultracold Gases
• Strongly interacting bosons in a disordered optical lattice
• Confinement-induced resonance in quasi-one-dimensional systems under transversely anisotropic confinement
• Quantum fluctuations and collective oscillations of a Bose-Einstein condensate in a 2D optical lattice
• Green's function approach to the Bose-Hubbard model with disorder

Cited by in corpus (2)

• Nonuniversal Equation of State of a Quasi-2D Bose Gas in Dimensional Crossover
• Interaction-Induced Dimensional Crossover through Full 3D to 1D