Correlated photon pair generation in low-loss double-stripe silicon   nitride waveguides
  We demonstrate correlated photon pair generation via spontaneous four-wave mixing in a low-loss double-stripe silicon nitride waveguide with a coincidence-to-accidental ratio over 10. The coincidence-to-accidental ratio is limited by spontaneous Raman scattering, which can be mitigated by cooling in the future. This demonstration suggests that this waveguide structure is a potential platform to develop integrated quantum photonic chips for quantum information processing. 
Xiang Zhang, Yanbing Zhang, Chunle Xiong and Benjamin J. Eggleton
physics.optics