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arXiv · 2512.13462

Wigner function negativity in a classical model of quantum light

Brian R. La Cour
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Abstract

The presence of negative values in the Wigner quasiprobability distribution is deemed one of the hallmarks of nonclassical phenomena in quantum systems. Here we demonstrate a classical model of squeezed light that, when combined with post-selection on amplitude threshold-crossing detection events, is capable of reproducing observed behavior of single-photon added coherent states. In particular, a classical model of balanced homodyne detection and standard tomographic techniques are used to infer the density matrix in the Fock basis. The resulting Wigner functions exhibit negatively for photon-added vacuum and weak coherent states.

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Brian R. La Cour. 2025-12-15. Wigner function negativity in a classical model of quantum light. https://doi.org/10.1142/s021947752540036x

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