High visibility two photon interference of frequency time entangled   photons generated in a quasi phase matched AlGaAs waveguide
  We demonstrate experimentally the frequency time entanglement of photon pairs produced in a CW pumped quasi phased matched AlGaAs superlattice waveguide. A visibility of 96.0+-0.7% without background subtraction has been achieved, which corresponds the violation of Bell inequality by 52 standard deviations. 
Peyman Sarrafi, Eric Y. Zhu, Barry M. Holmes, David C. Hutchings,   Stewart Aitchison, Li Qian
quant-ph physics.optics