Compact Cavity-Enhanced Single-Photon Generation with Hexagonal Boron Nitride
Tobias Vogl, Ruvi Lecamwasam, B. C. Buchler, Yuerui Lu, Ping Koy Lam · ACS Photonics · 2019
Sources of pure and indistinguishable single-photons are critical for near-future optical quantum technologies. Recently, color centers hosted by two-dimensional hexagonal boron nitride (hBN) have emerged as a promising platform for high luminosity room temperature single-photon sources. Despite the brightness of the emitters, the spectrum is rather broad and the single-photon purity is not sufficient for practical quantum information processing. Here, we report integration of such a quantum emitter hosted by hBN into a tunable optical microcavity. A small mode volume of the order of λ 3 allows us to Purcell enhance the fluorescence, with the observed excited state lifetime shortening. The cavity significantly narrows the spectrum and improves the single-photon purity by suppression of off-resonant noise. The complete device, including all optics, driving electronics, and control units, is compact and integrated in a small volume of 10 × 10 × 10 cm 3, allowing for portable usage in mobile applications.