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arXiv:1107.4305 · Physical Review Letters

Experimental Test of the Quantum Non-Gaussian Character of a Heralded Single-Photon State

Miroslav Ježek, Ivo Straka, Michal Mičuda, Miloslav Dušek, Jaromı́r Fiurášek, Radim Filip

Published Nov 15, 2011• 86 citations
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Abstract

We report on the experimental verification of quantum non-Gaussian character of a heralded single-photon state with a positive Wigner function. We unambiguously demonstrate that the generated state cannot be expressed as a mixture of Gaussian states. Sufficient information to witness the quantum non-Gaussian character is obtained from a standard photon anticorrelation measurement.

DOI
10.1103/physrevlett.107.213602

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We propose a criterion giving a sufficient condition for quantum states of a harmonic oscillator not to be expressible as a convex mixture of Gaussian states. This nontrivial property is inherent to, e.g., a single-photon state and the criterion thus allows one to reveal a signature of the state even in quantum states with a positive Wigner function. The criterion relies on directly measurable photon number probabilities and enables detection of this manifestation of a single-photon state in quantum states produced by solid-state single-photon sources in a weak coupling regime.
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