Quantum State Reconstruction of the Single-Photon Fock State

Fachbereich Physik, Universität Konstanz, D-78457 Konstanz, Germany.
Physical Review Letters (Impact Factor: 7.51). 07/2001; 87(5):050402. DOI: 10.1103/PhysRevLett.87.050402
Source: PubMed


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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    • "As such, its statistics feature substantial yet temporally fluctuating bunching of photons, making it a perfect test case for the photon number resolving capabilities of our setup. ii) Heralded single photons from a spontaneous parametric down conversion source, which approximately represent the ideal scenario of single-photon Fock states [31]. In the multiplexer, classical coherent states |ψ in = |α are split into eight spatially separated coherent states of equal amplitude, i.e. |ψ out = "
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    • "In Fig. 2(b), the quadrature samples and their histogram corresponding to the envelope function ψ(t) are presented. There is a dip at the center of the histogram, which is a characteristic of a single-photon state [17] [18]. By performing maximum likelihood estimation on the quadrature distribution [35], we obtained the Wigner function [Fig. "
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