Photostable molecules on chip: integrated single photon sources for quantum technologies

The on-chip integration of quantum light sources and nonlinear elements poses a serious challenge to the development of a scalable platform for quantum information and communication. In this work we demonstrate the potential of a novel hybrid technology which combines single organic molecules as quantum emitters and dielectric chips, consisting of ridge waveguides and grating far-field couplers. Dibenzoterrylene molecules in thin anthracene crystals exhibit long-term photostability, easy fabrication methods and life-time limited emission at cryogenic temperatures. We couple such single emitters to silicon nitride ridge waveguide with a branching ratio of up to \SI{40\pm 3}{\percent}, considering both propagation directions. Single wave-guided photons can be readily processed on-chip or efficiently extracted into a quasi-gaussian mode in free space.