Resolved-sideband Raman cooling to the ground state of an optical   lattice
  We trap neutral Cs atoms in a two-dimensional optical lattice and cool them close to the zero-point of motion by resolved-sideband Raman cooling. Sideband cooling occurs via transitions between the vibrational manifolds associated with a pair of magnetic sublevels and the required Raman coupling is provided by the lattice potential itself. We obtain mean vibrational excitations \bar{n}_x \approx \bar{n}_y \approx 0.01, corresponding to a population \sim 98% in the vibrational ground state. Atoms in the ground state of an optical lattice provide a new system in which to explore quantum state control and subrecoil laser cooling 
S. E. Hamann, D. L. Haycock, G. Klose, P. H. Pax, I. H. Deutsch and P.   S. Jessen