Integration of hBN Quantum Emitters in Monolithically Fabricated Waveguides

Hexagonal boron nitride (hBN) is gaining interest for potential applications in integrated quantum nanophotonics. Yet, to establish hBN as an integrated photonic platform several cornerstones must be established, including the integration and coupling of quantum emitters to photonic waveguides. Supported by simulations, we study the approach of monolithic integration, which is expected to have coupling efficiencies that are similar to 4 times higher than those of a conventional hybrid stacking strategy. We then demonstrate the fabrication of such devices from hBN and showcase the successful integration of hBN single photon emitters with a monolithic waveguide. We demonstrate the coupling of single photons from the quantum emitters to the waveguide modes and collection from on-chip grating couplers. Our results build a general framework for monolithically integrated hBN single photon emitter and will facilitate future works toward on-chip integrated quantum photonics with hBN.