Hannover 2013 – wissenschaftliches Programm
Q 67.1: Vortrag
Freitag, 22. März 2013, 14:00–14:15, E 214
External vs internal spin squeezing. How to tell them apart? — Giuseppe Vitagliano1, •Zoltan Zimboras1, Philipp Hyllus1, Inigo Egusquiza1, and Geza Toth1,2,3 — 1Theoretical Physics, University of the Basque Country UPV/EHU, E-48080 Bilbao, Spain — 2IKERBASQUE, Basque Foundation for Science, E-48011 Bilbao, Spain — 3Wigner Research Centre for Physics, H-1525 Budapest, Hungary
Spin squeezing with collective angular momentum operators is studied for an ensemble of atoms with a local spin larger than 1/2. In these systems, unlike the case of spin-1/2 ensembles, it is possible to carry out internal spin squeezing: only the local spin of each atom is squeezed, while there is no correlation between the atoms. We discuss the possibility of introducing entanglement conditions that can identify whether the ensemble of atoms is in such an internal squeezed state or there is genuine inter-particle spin squeezing, which we term external squeezing. Also the detection of internal and external squeezing with possible collective measurements in actual experiments is addressed.