Optimized entangled photon pair generation via intermodal four-wave mixing in a telecommunication-length few-mode fiber

We report our recent progress in generating and verifying entangled photon pairs in a telecommunication-length few-mode fiber using spontaneous four-wave mixing in a non-degenerate pump configuration. We demonstrate through seeding the desired four-wave mixing effect for pair production in the presence of a strong mode-coupling when using integrated mode multiplexers known as photonic lanterns. The mode content and phase-matching requirements were validated through computations and experiments. We discuss the challenges and requirements for phase matching and photon visibility without modifying the fiber structure. This work represents our first steps toward an efficient tunable source of entangled photons for space division multiplexing applications.