Maximal entanglement of two spinor Bose-Einstein condensates

Starting with two weakly coupled antiferromagnetic spinor condensates, we show that by changing the sign of the coefficient of the spin interaction, U₂, via an optically induced Feshbach resonance, one can create an entangled state consisting of two anticorrelated ferromagnetic condensates. This state is maximally entangled and a generalization of the Bell state from two anticorrelated spin-$1∕2$ particles to two anticorrelated spin-$N∕2$ atomic samples, where N is the total number of atoms.