Quantum Statistics of the Squeezed Vacuum by Measurement of the Density Matrix in the Number State Representation

Abstract
We report the reconstruction of the quantum state of squeezed vacuum generated by a continuous-wave optical parametric amplifier. Homodyne detection and tomographic reconstruction methods were used to obtain the density matrix in the Fock (number state) representation. The photon number distribution exhibits odd-even oscillations, a manifestation of the photon pair production in the second-order nonlinear medium.