  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.
