Towards a Fock-States tomographic reconstruction

We present the experimental approach to the determination of the Fock-State s density matrix via the optical homodyne tomography. The single photon sta te is generated by Spontaneous Parametric Down Conversion (SPDC) in a nonli near crystal pumped by the Second Harmonic of a picosecond dye laser. The f undamental 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 singl e-photon state and, in the future, of the n-photon state. The experimental determination of the field state prepared in a coherent state with differen t mean photon numbers is also presented.