Physical Review A
Vortex lattices in fast rotating Bose-Einstein condensates between the Thomas-Fermi and the lowest-Landau-level regimes
Zhongzhou Chen, Changru Ma, Yong-li Ma
Abstract
We present an explicit analytical analysis of the ground state of vortex lattice structures, based on a minimization of the Gross-Pitaevskii energy functional in a fast rotating Bose-Einstein condensate between the Thomas-Fermi and the lowest-Landau-level regimes. By a Bogoliubov-like transformation we find that the coarse-grained average of the atomic density varies as ${[1\ensuremath{-}({x}^{2}+{y}^{2})∕{R}_{\ensuremath{\perp}}^{2}]}^{3∕2}$ in the $xy$ plane, and that the vortices form an almost regular triangular lattice. Our variational calculation is quantitatively and qualitatively consistent with recent analytical, numerical, and experimental data.