Optical nanocavities enable a strong interaction between single photons and single emitters. An appealing
application is the construction of a quantum interface for photonic and solid state qubits. Since the material of
the solid state qubit is often dierent from the nanocavity, there has been considerable interest in combining the
two in a hybrid architecture. We describe our recent development of such a hybrid interface based a Gallium
Phosphide photonic crystal nanocavity that is scanned and deterministically coupled to single emitters on a
surface. The technique is used to couple the cavity to the nitrogen vacancy center in diamond, an emitter system
with optically accessible electron spins and the ability to transfer electronic spin states to nuclear spins.