Generating single photons on-chip for integrated implementations of photonic quantum information processing remains challenging. Furthermore, photon-pair sources based on four-wave mixing in silicon waveguides have the additional difficulty that the pump laser can generate noise in the same spectral band as the photon pairs. In this paper, the authors address the challenge of separating photon pairs produced as desired in sections of waveguide designed for four-wave mixing from unwanted photon pairs created as the pump light is routed around the chip. By engineering the dispersion of a "generation" section in a narrow strip waveguide to be flatter than that of "routing" sections in shallow ridge waveguides and driving the process with a pair of non-degenerate pump lasers, the desired photon pairs are produced over a broader bandwidth than noise photons. The authors then use wavelength division multiplexing to isolate most of the noise in a narrow band while delivering photon pairs in two channels detuned to longer and shorter wavelengths.
You must log in
to add comments.