Divergence of the entanglement range in low-dimensional quantum systems

@article{citeulike:2502784, abstract = {We study the pairwise entanglement close to separable ground states of a class of one-dimensional quantum spin models. At T=0 we find that such ground states separate regions, in the space of the Hamiltonian parameters, which are characterized by qualitatively different types of entanglement, namely parallel and antiparallel entanglement; we further demonstrate that the range of the concurrence diverges while approaching separable ground states, therefore evidencing that such states, with uncorrelated fluctuations, are reached by a long range reshuffling of the entanglement. We generalize our results to the analysis of quantum phase transitions occurring in bosonic and fermionic systems. Finally, the effects of finite temperature are considered: At T>0 we evidence the existence of a region where no pairwise entanglement survives, so that entanglement, if present, is genuinely multipartite.}, author = {Amico, L. and Baroni, F. and Fubini, A. and Patan\`e, D. and Tognetti, V. and Verrucchi, Paola }, citeulike-article-id = {2502784}, doi = {http://dx.doi.org/10.1103/PhysRevA.74.022322}, journal = {Physical Review A (Atomic, Molecular, and Optical Physics)}, keywords = {2006, entanglement, quantum\_magnetism, quantum\_world, verrucchi}, number = {2}, posted-at = {2008-03-10 17:44:27}, priority = {2}, publisher = {APS}, title = {Divergence of the entanglement range in low-dimensional quantum systems}, url = {http://dx.doi.org/10.1103/PhysRevA.74.022322}, volume = {74}, year = {2006} }

TY - JOUR ID - citeulike:2502784 L3 - citeulike-article-id:2502784 TI - Divergence of the entanglement range in low-dimensional quantum systems JF - Physical Review A (Atomic, Molecular, and Optical Physics) VL - 74 IS - 2 PB - APS N2 - We study the pairwise entanglement close to separable ground states of a class of one-dimensional quantum spin models. At T=0 we find that such ground states separate regions, in the space of the Hamiltonian parameters, which are characterized by qualitatively different types of entanglement, namely parallel and antiparallel entanglement; we further demonstrate that the range of the concurrence diverges while approaching separable ground states, therefore evidencing that such states, with uncorrelated fluctuations, are reached by a long range reshuffling of the entanglement. We generalize our results to the analysis of quantum phase transitions occurring in bosonic and fermionic systems. Finally, the effects of finite temperature are considered: At T>0 we evidence the existence of a region where no pairwise entanglement survives, so that entanglement, if present, is genuinely multipartite. KW - 2006 KW - entanglement KW - quantum_magnetism KW - quantum_world KW - verrucchi AU - Amico, L AU - Baroni, F AU - Fubini, A AU - Patan\`e, D AU - Tognetti, V AU - Verrucchi, Paola PY - 2006/// UR - http://dx.doi.org/10.1103/PhysRevA.74.022322 ER -