Quantum control of spin-correlations in ultracold lattice gases
  We demonstrate that it is possible to prepare a lattice gas of ultracold atoms with a desired non-classical spin-correlation function using atom-light interaction of the kind routinely employed in quantum spin polarization spectroscopy. Our method is based on quantum non-demolition (QND) measurement and feedback, and allows in particular to create on demand exponentially or algebraically decaying correlations, as well as a certain degree of multi-partite entanglement. 
P. Hauke, R. J. Sewell, M. W. Mitchell, M. Lewenstein
quant-ph cond-mat.quant-gas