Single photon emitters (SPEs) are critical building blocks needed for quantum science and technology. For practical applications, room-temperature solid-state platforms are critically demanded. To scale up quantum information processing using, for example, wavelength division multiplexing quantum key distribution, a large tuning range beyond emission line width of single photon energy is required. Stark effect can tune the single photon energy by an electric field. However, it has been achieved only at cryogenic temperature to pursue a shift larger than emission line width. A large Stark tuning beyond emission line width at room temperature still remains elusive. Here we report the first room-temperature Stark effect of SPEs with a giant Stark shift of single photon energy up to 43 meV/(V/nm), largest among all previous color center emitters. Such a giant Stark shift is 4-fold larger than its line width at room temperature, demonstrated by exploiting hBN color centers. Moreover, the intrinsic broken symmetries are determined via angle-resolved Stark effect, for the first time, by the orientation of the electric permanent dipole moment in the solid-state SPE, which is unachievable in traditional optical polarization measurement. The remarkable Stark shift discovered here and the significant advance in understanding its atomic structure pave a way toward the scalable solid-state on-chip quantum communication and computation at room temperature.
Keywords: Stark effect; color center; hexagonal boron nitride; permanent electric dipole moment; single photon emitter; symmetry breaking.