Berlin 2001 – scientific programme
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Q: Quantenoptik
Q 25: Quantum Effects II
Q 25.2: Talk
Thursday, April 5, 2001, 16:00–16:15, H 3010
Cooperative effects between trapped ions — •Joachim von Zanthier1, Christoph Skornia1,2, Girish S. Agarwal1,3, Ernst Werner2, and Herbert Walther1 — 1Max-Planck-Institut für Quantenoptik and Sektion Physik der LMU München, D-85748 Garching, Germany — 2Institut für Theoretische Physik, Universität Regensburg, D-93040 Regensburg, Germany — 3Physical Research Laboratory, Navrangpura, Ahmedabad-380 009, India
There has been a controversy whether cooperative effects show up in the quantum jump statistics of atoms or ions placed in the vicinity of each other and not observed individually. Cooperative effects have been reported by Sauter et al. [1] and Block et al. [2] but experiments performed by Itano et al. [3] and later by Donald et al. [4] did not display deviation from the photon statistics of independently radiating ions. Lewenstein et al. [5] proved in a theoretical paper that the quantum jump statistics of 3-level systems coherently excited on the fast transition is independent from ion distance. It remained unclear why the dipole-dipole interaction has no effect. We find by a Quantum Monte Carlo calculation that the entanglement between the ions is suppressed by a Quantum Zeno effect on the fast transition. In case of an individual ion detection it can be shown that the dipole-dipole interaction can nevertheless be determined.
[1] Th. Sauter et al., Opt. Comm. 60, 287, (1986)
[2] M. Block et al., Eur. Phys. J. D 7, 461, (1999)
[3] W. M. Itano et al., Phys. Rev. A, 38, 559, (1988)
[4] C. J. S. Donald et al., Europhys. Lett., 51, 388, (2000)
[5] M. Lewenstein et al., IEEE J. Quantum Electr., 24, 1403, (1988)