Photon noise limited radiation detection with lens-antenna coupled   Microwave Kinetic Inductance Detectors
  Microwave Kinetic Inductance Detectors (MKIDs) have shown great potential for sub-mm instrumentation because of the high scalability of the technology. Here we demonstrate for the first time in the sub-mm band (0.1...2 mm) a photon noise limited performance of a small antenna coupled MKID detector array and we describe the relation between photon noise and MKID intrinsic generation-recombination noise. Additionally we use the observed photon noise to measure the optical efficiency of detectors to be 0.8+-0.2. 
S. J. C. Yates, J. J. A. Baselmans, A. Endo, R. M. J. Janssen, L.   Ferrari, P. Diener, and A. M. Baryshev
astro-ph.IM