Demonstration of a bright and compact source of tripartite nonclassical light

We experimentally demonstrate the nonclassical photon number correlations expected in tripartite
continuous-variable states obtained by parametric processes. Our scheme involves a single nonlinear crystal,
where two interlinked parametric interactions take place simultaneously, and represents a bright and compact
source of a sub-shot-noise tripartite light field. We analyze the effects of the pump intensities on the numbers
of detected photons and on the amount of noise reduction in some detail, thus demonstrating a good agreement
between the experimental data and a single-mode theoretical description.