%0 Journal Article
%T Entangled Rings
%A Kevin M. O'Connor
%A William K. Wootters
%J Physics
%D 2000
%I arXiv
%R 10.1103/PhysRevA.63.052302
%X Consider a ring of N qubits in a translationally invariant quantum state. We ask to what extent each pair of nearest neighbors can be entangled. Under certain assumptions about the form of the state, we find a formula for the maximum possible nearest-neighbor entanglement. We then compare this maximum with the entanglement achieved by the ground state of an antiferromagnetic ring consisting of an even number of spin-1/2 particles. We find that, though the antiferromagnetic ground state does not maximize the nearest-neighbor entanglement relative to all other states, it does so relative to other states having zero z-component of spin.
%U http://arxiv.org/abs/quant-ph/0009041v3