We propose an on-chip source of entangled photon pairs that uses an arrayed-waveguide grating (AWG) with multiple nonlinear input waveguides as correlated photon pair sources. The AWG wavelength-demultiplexes photon pairs created in input waveguides and simultaneously produces a high-dimensional entangled state encoded in the optical path. We implemented the device with a monolithic silicon-silica waveguide integration platform and demonstrated the entanglement of two dimensions in a proof-of-principle experiment.
@article{arxiv.1711.01738,
title = {Generation of entangled photons using an arrayed waveguide grating},
author = {Nobuyuki Matsuda and Hidetaka Nishi and Peter Karkus and Tai Tsuchizawa and Koji Yamada and William John Munro and Kaoru Shimizu and Hiroki Takesue},
journal= {arXiv preprint arXiv:1711.01738},
year = {2017}
}