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arXiv · 1307.3070

Optimal probabilistic measurement of phase

Petr Marek
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Abstract

When measuring phase of quantum states of light, the optimal single-shot measurement implements projection on the un-physical phase states. If we want to improve the precision further we need to accept a reduced probability of success, either by implementing a probabilistic measurement or by probabilistically manipulating the measured quantum state by means of noiseless amplification. We analyze the limits of this approach by finding the optimal probabilistic measurement which, for a given rate of success, maximizes the precision with which the phase can be measured.

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Petr Marek. 2013-07-11. Optimal probabilistic measurement of phase. https://doi.org/10.1103/physreva.88.045802

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