Toroidal optical dipole traps for atomic Bose-Einstein condensates using   Laguerre-Gaussian beams
  We theoretically investigate the use of red-detuned Laguerre-Gaussian (LG) laser beams of varying azimuthal mode index for producing toroidal optical dipole traps in two-dimensional atomic Bose-Einstein condensates. Higher-order LG beams provide deeper potential wells and tighter confinement for a fixed toroid radius and laser power. Numerical simulations of the loading of the toroidal trap from a variety of initial conditions is also given. 
E. M. Wright, J. Arlt, and K. Dholakia