Quantized Vortex States of Strongly Interacting Bosons in a Rotating Optical Lattice

Abstract

Bose gases in rotating optical lattices combine two important topics in quantum physics: superfluid rotation and strong correlations. In this paper, we examine square two-dimensional systems at zero temperature comprised of strongly repulsive bosons with filling factors of less than one atom per lattice site. The entry of vortices into the system is characterized by jumps of 2 pi in the phase winding of the condensate wavefunction. A lattice of size L X L can have at most L-1 quantized vortices in the lowest Bloch band. In contrast to homogeneous systems, angular momentum is not a good quantum number since the continuous rotational symmetry is broken by the lattice. Instead, a quasi-angular momentum captures the discrete rotational symmetry of the system. Energy level crossings indicative of quantum phase transitions are observed when the quasi-angular momentum of the ground-state changes.

12 Pages, 13 Figures, Version 1

References in corpus (4)

• Vortex configurations of bosons in an optical lattice
• Vortex-Peierls States in Optical Lattices
• Pinning and collective modes of a vortex lattice in a Bose-Einstein condensate
• Vortex liquids and vortex quantum Hall states in trapped rotating Bose gases

Cited by in corpus (7)

• Topological Winding and Unwinding in Metastable Bose-Einstein Condensates
• Hall effects in Bose-Einstein condensates in a rotating optical lattice
• Edge Transport in 2D Cold Atom Optical Lattices
• Quasi-angular momentum of Bose and Fermi gases in rotating optical lattices
• Rotating states for trapped bosons in an optical lattice
• Mott-Insulator Transition for Ultracold Fermions in Two-Dimensional Optical Lattices
• Fast mode of rotating atoms in one-dimensional lattice rings