caa a22 4500 445858753 CHVBK 20180317145436.0 cr unu---uuuuu 170323e20110701xx s 000 0 eng 10.1007/s10946-011-9220-4 doi (NATIONALLICENCE)springer-10.1007/s10946-011-9220-4 Evaluation of entanglement measures in spin systems with the random phase approximation [Elektronische Daten] [N. Canosa, J. Matera, R. Rossignoli] We discuss a general formalism based on the mean field plus random phase approximation (RPA) for the evaluation of entanglement measures in the ground state of spin systems. The method provides a tractable scheme for determining the entanglement entropy as well as the negativity of finite subsystems, which becomes analytic in the case of systems with translational invariance, in one or D dimensions. The approach improves as the spin increases, and also as the interaction range or connectivity increases. Illustrative results for different types of entanglement entropies (single site, block and comb) in the ground state of a small spin lattice with ferromagnetic type XY couplings in a transverse field are shown and compared with the exact numerical result. Effects arising from symmetry breaking at the mean field level are also discussed. Springer Science+Business Media, Inc., 2011 quantum entanglement nationallicence random phase approximation nationallicence bosonization nationallicence Canosa N. Departamento de Física - IFLP, Universidad Nacional de La Plata, 1900, C.C. 67 La Plata, Argentina aut Matera J. Departamento de Física - IFLP, Universidad Nacional de La Plata, 1900, C.C. 67 La Plata, Argentina aut Rossignoli R. Departamento de Física - IFLP, Universidad Nacional de La Plata, 1900, C.C. 67 La Plata, Argentina aut Journal of Russian Laser Research Springer US; http://www.springer-ny.com 32/4(2011-07-01), 322-330 1071-2836 32:4<322 2011 32 10946 https://doi.org/10.1007/s10946-011-9220-4 text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1007/s10946-011-9220-4 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Canosa N. Departamento de Física - IFLP, Universidad Nacional de La Plata, 1900, C.C. 67 La Plata, Argentina aut NATIONALLICENCE 700 1- Matera J. Departamento de Física - IFLP, Universidad Nacional de La Plata, 1900, C.C. 67 La Plata, Argentina aut NATIONALLICENCE 700 1- Rossignoli R. Departamento de Física - IFLP, Universidad Nacional de La Plata, 1900, C.C. 67 La Plata, Argentina aut NATIONALLICENCE 773 0- Journal of Russian Laser Research Springer US; http://www.springer-ny.com 32/4(2011-07-01), 322-330 1071-2836 32:4<322 2011 32 10946 Metadata rights reserved Springer special CC-BY-NC licence nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer