Optically Addressing Single Rare-Earth Ions in a Nanophotonic Cavity

This is the authors' abstract. We don't add key points for this paper.

We demonstrate optical probing of spectrally resolved single Nd³⁺ rare-earth ions in yttrium orthovanadate. The ions are coupled to a photonic crystal resonator and show strong enhancement of the optical emission rate via the Purcell effect, resulting in near radiatively limited single photon emission. The measured high coupling cooperativity between a single photon and the ion allows for the observation of coherent optical Rabi oscillations. This could enable optically controlled spin qubits, quantum logic gates, and spin-photon interfaces for future quantum networks.