Quantum homodyne tomography of the single-photon Fock state

Quantum states containing a definite number of photons (Fock states) are fundamental states of the quantized electromagnetical field. They are highly non-classical and reveal the wave-particle duality of light most strikingly. We present an experiment on characterization of the singlephoton Fock state using the method of quantum homodyne tomography. The single-photon pulses were prepared using conditional measurements on photon pairs born in the process of parametric fluorescence. The probability distribution of the phase-averaged electrical field amplitudes with a strong non-Gaussian shape is obtained with the total detection efficiency of 55%. The phase-averaged Wigner function reconstructed from this distribution shows a minimum at the origin of the phase space reaching a classicaly impossible negative value.