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Quantum state reconstruction of the single-photon Fock state

A. I. Lvovsky·H. Hansen·T. Aichele·O. Benson·J. Mlynek·S. Schiller
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Abstract

We have reconstructed the quantum state of optical pulses containing single photons using the method of phase-randomized pulsed optical homodyne tomography. The single-photon Fock state |1> was prepared using conditional measurements on photon pairs born in the process of parametric down-conversion. A probability distribution of the phase-averaged electric field amplitudes with a strongly non-Gaussian shape is obtained with the total detection efficiency of (55+-1)%. The angle-averaged Wigner function reconstructed from this distribution shows a strong dip reaching classically impossible negative values around the origin of the phase space.

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A. I. Lvovsky, H. Hansen, T. Aichele, O. Benson, J. Mlynek, S. Schiller. 2001-06-15. Quantum state reconstruction of the single-photon Fock state. https://doi.org/10.1103/physrevlett.87.050402

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