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arXiv · 0909.1887

Non-negative Wigner functions for orbital angular momentum states

I. Rigas·L. L. Sanchez-Soto·A. B. Klimov·J. Rehacek·Z. Hradil
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Abstract

The Wigner function of a pure continuous-variable quantum state is non-negative if and only if the state is Gaussian. Here we show that for the canonical pair angle and angular momentum, the only pure states with non-negative Wigner functions are the eigenstates of the angular momentum. Some implications of this surprising result are discussed.

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I. Rigas, L. L. Sanchez-Soto, A. B. Klimov, J. Rehacek, Z. Hradil. 2009-09-10. Non-negative Wigner functions for orbital angular momentum states. https://doi.org/10.1103/physreva.81.012101

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