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Observation of the Quantum Zeno and Anti-Zeno effects in an unstable system

M. C. Fischer·B. Gutierrez-Medina·M. G. Raizen
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Abstract

We report the first observation of the Quantum Zeno and Anti-Zeno effects in an unstable system. Cold sodium atoms are trapped in a far-detuned standing wave of light that is accelerated for a controlled duration. For a large acceleration the atoms can escape the trapping potential via tunneling. Initially the number of trapped atoms shows strong non-exponential decay features, evolving into the characteristic exponential decay behavior. We repeatedly measure the number of atoms remaining trapped during the initial period of non-exponential decay. Depending on the frequency of measurements we observe a decay that is suppressed or enhanced as compared to the unperturbed system.

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M. C. Fischer, B. Gutierrez-Medina, M. G. Raizen. 2001-04-08. Observation of the Quantum Zeno and Anti-Zeno effects in an unstable system. https://doi.org/10.1103/physrevlett.87.040402

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