Analytic Relations between Localizable Entanglement and String Correlations in Spin Systems

L. Campos Venuti, M. Roncaglia
2005 Physical Review Letters  
We study the relation between the recently defined localizable entanglement and generalized correlations in quantum spin systems. Differently from the current belief, the localizable entanglement is always given by the average of a generalized string. Using symmetry arguments we show that in most spin 1/2 and spin 1 systems the localizable entanglement reduces to the spin-spin or string correlations, respectively. We prove that a general class of spin 1 systems, which includes the Heisenberg
more » ... el, can be used as perfect quantum channel. These conclusions are obtained in analytic form and confirm some results found previously on numerical grounds.
doi:10.1103/physrevlett.94.207207 pmid:16090283 fatcat:2n7ya7duo5gl7epfcii232djlu