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Purification through Zeno-like Measurements

Hiromichi Nakazato·Tomoko Takazawa·Kazuya Yuasa
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Abstract

A series of frequent measurements on a quantum system (Zeno-like measurements) is shown to result in the ``purification'' of another quantum system in interaction with the former. Even though the measurements are performed on the former system, their effect drives the latter into a pure state, irrespectively of its initial (mixed) state, provided certain conditions are satisfied.

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Hiromichi Nakazato, Tomoko Takazawa, Kazuya Yuasa. 2003-01-08. Purification through Zeno-like Measurements. https://doi.org/10.1103/physrevlett.90.060401

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