Very Large and Reversible Stark-Shift Tuning of Single Emitters in Layered Hexagonal Boron Nitride

Bright, solid-state single-photon emitters are essential for scalable quantum photonic technology. Room-temperature switching of such emitters into and out of resonance, which is key for quantum functionality, requires reversible and wide-range tuning, but such an emitter has remained elusive. The authors report electrostatic control of a huge spectral shift for individually selected emitters in h-BN. Their method, based on applying an electric field via a conductive tip, is simple, yet allows for a systematic analysis of crucial properties of individual solid-state emitters. This appears to be a large step forward in integrated quantum optics.