Abstract

Light beams endowed with non-classical correlations are crucial resources for quantum technology and find applications in quantum communication, imaging and precision measurement. In turns their full characterization represents an important tool for the design of quantum information processing protocols in realistic conditions. Remarkably, entangled states produced by OPOs are Gaussian states and thus may be fully characterized by the first two statistical moments of the field modes [1]; in turn, the CM contains the complete information about entanglement. Although the correlation properties of OPO signals have been widely investigated, no proper CM reconstruction has been experimentally performed so far, so that a priori hypotheses on the measured state were required to mend the effect of non-physical CM entries or deviations from a proper CM [2-4].

© 2009 IEEE