  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 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 coupling of single
photons from the quantum emitters to the waveguide modes and on-chip detection.
Our results build a general framework for monolithically integrated hBN single
photon emitter and will facilitate future works towards on-chip integrated
quantum photonics with hBN.
