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A quantum measurement of the spin direction

G. M. D'Ariano·P. Lo Presti·M. F. Sacchi
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Abstract

We give a first physical model for the quantum measurement of the spin direction. It is an Arthurs-Kelly model that involves a kind of magnetic-dipole interaction of the spin with three modes of radiation. We show that in a limit of infinite squeezing of radiation the optimal POVM for the measurement of the spin direction is achieved for spin 1/2.

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G. M. D'Ariano, P. Lo Presti, M. F. Sacchi. 2001-10-10. A quantum measurement of the spin direction. https://doi.org/10.1016/s0375-9601(01)00809-x

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