Decoherence in Bose-Einstein condensates: Towards bigger and better Schrodinger cats - art. no. 013607

We consider a quantum superposition of Bose-Einstein condensates (BEC's) in two immiscible internal states. A decoherence rate for the resulting Schro dinger cat is calculated and shown to be a significant threat to this macro scopic quantum superposition of BEC's. An experimental scenario is outlined where the decoherence rate due to the thermal cloud is dramatically reduce d thanks to trap engineering and "symmetrization" of the environment, which allow the Schrodinger cat to be an approximate painter state.