Observation of near-infrared sub-Poissonian photon emission in hexagonal boron nitride at room temperature

The generation of non-classical light states in the near-infrared (NIR) is important for a number of photonic quantum technologies. Here, we report the first experimental observation of sub-Poissonian NIR (1.24 eV) light emission from defects in a 2D hexagonal boron nitride (hBN) sheet at room temperature. Photoluminescence statistics shows g(2)(0) = 0.6, which is a signature of the quantum nature of the emission. Density functional-theory calculations, at the level of the generalized gradient approximation, for the negatively charged nitrogen anti-site lattice defects are consistent with the observed emission energy. This work demonstrates that the defects in hBN could be a promising platform for single-photon generation in the NIR.