Super-poissonian photon statistics and correlations between pump and   probe fields in Electromagnetically Induced Transparency
  We have measured the photon statistics of pump and probe beams after interaction with Rb atoms in a situation of Electromagnetically Induced Transparency. Both fields present super-poissonian statistics and their intensities become correlated, in good qualitative agreement with theoretical predictions in which both fields are treated quantum-mechanically. The intensity correlations measured are a first step towards the observation of entanglement between the fields. 
C. L. Garrido Alzar, L. S. Cruz, J. G. Aguirre Gomez, M. Franca   Santos, and P. Nussenzveig (Instituto de Fisica, Universid...