  Optical parametric downconversion has proven to be a valuable source of
nonclassical light. The process is inherently able to produce twin beam
correlations along with individual intensity squeezing of either parametric
beam, when pumped far above threshold. Here, we present for the first time the
direct observation of intensity squeezing of -1.2 dB of each of the individual
parametric beams in parametric downconversion by use of a high quality
whispering gallery mode disk resonator. In addition we observed twin beam
quantum correlations of -2.7 dB with this cavity. Such resonators feature
strong optical confinement, and offer tunable coupling to an external optical
field. This work exemplifies the potential of crystalline whispering gallery
mode resonators in quantum and nonlinear optics and in particular for the
generation of quantum light. The simplicity of this device makes the
application of quantum light in various fields highly feasible.
