Towards a Fock-States Tomographic Reconstruction

We present the experimental approach to the determination of the Fock-States density matrix via the optical homodyne tomography. The single photon state is generated by Spontaneous Parametric Down Conversion (SPDC) in a nonlinear crystal pumped by the Second Harmonic of a picosecond dye laser. The fundamental frequency of the dye-laser realizes the local oscillator for the homodyne measurement. In this paper we describe the experimental apparatus and discuss the possibility to realize the quantum tomography of the single-photon state and, in the future, of the n-photon state. The experimental determination of the field state prepared in a coherent state with different mean photon numbers is also presented.