Natural entanglement in Bose-Einstein condensates
Christoph Simon · Physical Review A · 2002
It is shown that every zero-temperature Bose-Einstein condensate is a highly entangled state, as a consequence of the fact that the particles in a condensate are distributed over space in a coherent way. In particular, any two regions within a condensate of finite particle number are entangled. This entanglement does not depend on the distance between the two regions. Criteria for the presence of entanglement are derived in the context of interference experiments. For separable states there is a trade-off between fluctuations in particle number and interference visibility.