Proceedings of SPIE, the International Society for Optical Engineering/Proceedings of SPIE
Pattern-function quantum tomography: a tool for experimentally investigating the real state of radiation fields
A. Porzio, Virginia D’Auria, Salvatore Solimeno, Matteo G. A. Paris
Abstract
We have exploited pattern function quantum homodyne tomography (QHT) to enlight deviations from the Gaussian state for a squeezed vacuum field generated by a type-I below threshold OPO. This tomographic method allows to fully characterize the state without any a--priori assumption on its statistics. Applying pattern function QHT to the radiation outing a type-I below threshold OPO, we have measured photon number distributions different from those expected for a Gaussian field. Being the Wigner function and the quadrature marginal distribution Gaussian for a Gaussian field, the actual state has been analysed by looking at data variance and Kurtosis (0 for a Gaussian distribution) as a function of the quadrature angle θ. A clear deviation of the Kurtosis from zero has been found for different OPO cavities. This deviation increases as the threshold is approached.