Berlin 2014 – wissenschaftliches Programm
Q 37.3: Vortrag
Donnerstag, 20. März 2014, 11:00–11:15, Kinosaal
Many-particle entanglement in a spinor condensate — •Bernd Lücke1, Jan Peise1, Giuseppe Vitagliano2, Wolfgang Ertmer1, Luis Santos3, Géza Toth2, and Carsten Klempt1 — 1Institut für Quantenoptik, Leibniz Unviersität Hannover — 2Department of Theoretical Physics, The University of the Basque Country, Bilbao, Spain — 3Institut für theoretische Physik, Leibniz Unviersität Hannover
Ensembles of neutral atoms with entangled spins are a valuable resource for quantum enhanced metrology, quantum simulation and quantum information. Recently spin changing collisions in a Bose-Einstein condensate were established as a new tool to create such ensembles. Here we present a characterization of a quantum state produced by this mechanism. We show that the fluctuations in the z-component of the ensemble’s total spin are reduced by 12.4 dB compared to an unentangled coherent state. Meanwhile, the length of the total spin almost reaches its maximum achievable value of N/2. This shows that the state is close to a highly entangled Dicke state with a fluctuating total number of particles with up to 10000 87Rb atoms. We measure an optimal spin squeezing parameter of −11.4(5) dB and use newly derived methods to prove that the state contains at least genuine 28-particle entanglement.