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Optimization of a Neutron-Spin Test of the Quantum Zeno Effect

Paolo Facchi·Yoichi Nakaguro·Hiromichi Nakazato·Saverio Pascazio·Makoto Unoki·Kazuya Yuasa
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Abstract

A neutron-spin experimental test of the quantum Zeno effect (QZE) is discussed from a practical point of view, when the nonideal efficiency of the magnetic mirrors, used for filtering the spin state, is taken into account. In the idealized case the number N of (ideal) mirrors can be indefinitely increased, yielding an increasingly better QZE. By contrast, in a practical situation with imperfect mirrors, there is an optimal number of mirrors, N_opt, at which the QZE becomes maximum: more frequent measurements would deteriorate the performance. However, a quantitative analysis shows that a good experimental test of the QZE is still feasible. These conclusions are of general validity: in a realistic experiment, the presence of losses and imperfections leads to an optimal frequency N_opt, which is in general finite. One should not increase N beyond N_opt. A convenient formula for N_opt, valid in a broad framework, is derived as a function of the parameters characterizing the experimental setup.

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Paolo Facchi, Yoichi Nakaguro, Hiromichi Nakazato, Saverio Pascazio, Makoto Unoki, Kazuya Yuasa. 2003-01-15. Optimization of a Neutron-Spin Test of the Quantum Zeno Effect. https://doi.org/10.1103/physreva.68.012107

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