Decoherence in Bose-Einstein Condensates: towards Bigger and Better   Schroedinger Cats
  We consider a quantum superposition of Bose-Einstein condensates in two immiscible internal states. A decoherence rate for the resulting Schroedinger cat is calculated and shown to be a significant threat to this macroscopic quantum superposition of BEC's. An experimental scenario is outlined where the decoherence rate due to the thermal cloud is dramatically reduced thanks to trap engineering and "symmetrization" of the environment which allow for the Schroedinger cat to be an approximate pointer states. 
Diego A.R. Dalvit, Jacek Dziarmaga, and Wojciech H.Zurek