An optically resolvable Schr\"odinger's cat from Rydberg dressed cold   atom clouds
  In Rydberg dressed ultra-cold gases, ground state atoms inherit properties of a weakly admixed Rydberg state, such as sensitivity to long-range interactions. We show that through hyperfine-state dependent interactions, a pair of atom clouds can evolve into a spin and subsequently into a spatial Schr\"odinger's cat state: The pair, containing 20 atoms in total, is in a coherent superposition of two configurations, with cloud locations separated by micrometers. The mesoscopic nature of the superposition state can be proven with absorption imaging, while the coherence can be revealed though recombination and interference of the split wave packets. 
S. M\"obius, M. Genkin, A. Eisfeld, S. W\"uster and J.-M. Rost
physics.atom-ph quant-ph