EPR Beams and Photon Number Detector: Toward Synthesizing Optical   Nonlinearity
  We present the two kinds of experimental results. One is a continuous variable dense coding experiment, and the other is a photon number detector with high linearity response, the so called charge integration photon detector (CIPD). They can be combined together to be a potential tool for implementing the cubic phase gate which is an important gate element to synthesize the measurement induced nonlinearity for photonic quantum information processing. 
M. Sasaki, K. Wakui, J. Mizuno, M. Fujiwara, and M. Akiba