Mutual Unbiasedness in Coarse-Grained Continuous Variables.

Phys Rev Lett

Max-Planck-Institut für die Physik des Lichts, Staudtstraße 2, 91058 Erlangen, Germany.

Published: January 2018

The notion of mutual unbiasedness for coarse-grained measurements of quantum continuous variable systems is considered. It is shown that while the procedure of "standard" coarse graining breaks the mutual unbiasedness between conjugate variables, this desired feature can be theoretically established and experimentally observed in periodic coarse graining. We illustrate our results in an optics experiment implementing Fraunhofer diffraction through a periodic diffraction grating, finding excellent agreement with the derived theory. Our results are an important step in developing a formal connection between discrete and continuous variable quantum mechanics.

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http://dx.doi.org/10.1103/PhysRevLett.120.040403DOI Listing

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