Among a variety of layered materials used as building blocks in van der Waals heterostructures, hexagonal boron nitride (hBN) appears as an ideal platform for hosting optically-active defects owing to its large bandgap (∼6 eV). Here we study the optical response of a high-purity hBN crystal under green laser illumination. By means of photon correlation measurements, we identify individual defects emitting a highly photostable fluorescence under ambient conditions. A detailed analysis of the photophysical properties reveals a high quantum efficiency of the radiative transition, leading to a single photon source with very high brightness. These results illustrate how the wide range of applications offered by hBN could be further extended to photonic-based quantum information science and metrology.
@article{arxiv.1606.04124,
title = {Efficient single photon emission from a high-purity hexagonal boron nitride crystal},
author = {L. J. Martínez and T. Pelini and V. Waselowski and J. R. Maze and B. Gil and G. Cassabois and V. Jacques},
journal= {arXiv preprint arXiv:1606.04124},
year = {2016}
}