arXiv:quant-ph/0606110 · Physical Review A

Entanglement between atomic condensates in an optical lattice: Effects of interaction range

H. T. Ng, Keith R. Burnett

Published Feb 1, 2007• 15 citations

Abstract

We study the area-dependent entropy and two-site entanglement for two-state Bose-Einstein condensates in a two-dimensional optical lattice. We consider the case where the array of two-component condensates behaves like an ensemble of spin-half particles with the interaction to its nearest neighbors and next-nearest neighbors. We show how the Hamiltonian of their Bose-Einstein condensate lattice with nearest-neighbor and next-nearest-neighbor interactions can be mapped onto a harmonic lattice. We use this to determine the entropy and entanglement content of the lattice.

DOI: 10.1103/physreva.75.023601

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