Identifying carbon as the source of visible single-photon emission from hexagonal boron nitride

• Published in: Nature materials Vol. 20; no. 3; pp. 321 - 328
• Main Authors: Mendelson, Noah, Chugh, Dipankar, Reimers, Jeffrey R., Cheng, Tin S., Gottscholl, Andreas, Long, Hu, Mellor, Christopher J., Zettl, Alex, Dyakonov, Vladimir, Beton, Peter H., Novikov, Sergei V., Jagadish, Chennupati, Tan, Hark Hoe, Ford, Michael J., Toth, Milos, Bradac, Carlo, Aharonovich, Igor
• Format: Journal Article
• Language: English
• Published: London Nature Publishing Group UK 01.03.2021; Nature Publishing Group
• Subjects: 639/301/1019; 639/301/1019/1021; 639/301/1019/482; Biomaterials; Boron; Boron nitride; Carbon; Chemistry and Materials Science; Condensed Matter Physics; Defects; Emissions; Emitters; Ion implantation; Magnetic resonance; Materials Science; Nanotechnology; Optical and Electronic Materials; Optical properties; Photon emission; Photons; Room temperature
• ISSN: 1476-1122; 1476-4660; 1476-4660
• DOI: 10.1038/s41563-020-00850-y

Single-photon emitters (SPEs) in hexagonal boron nitride (hBN) have garnered increasing attention over the last few years due to their superior optical properties. However, despite the vast range of experimental results and theoretical calculations, the defect structure responsible for the observed emission has remained elusive. Here, by controlling the incorporation of impurities into hBN via various bottom-up synthesis methods and directly through ion implantation, we provide direct evidence that the visible SPEs are carbon related. Room-temperature optically detected magnetic resonance is demonstrated on ensembles of these defects. We perform ion-implantation experiments and confirm that only carbon implantation creates SPEs in the visible spectral range. Computational analysis of the simplest 12 carbon-containing defect species suggest the negatively charged V B C N − defect as a viable candidate and predict that out-of-plane deformations make the defect environmentally sensitive. Our results resolve a long-standing debate about the origin of single emitters at the visible range in hBN and will be key to the deterministic engineering of these defects for quantum photonic devices. Comparison of hexagonal boron nitride samples grown with different techniques and with varying carbon-doping content provides evidence that the defects emitting single photons in the visible range are carbon related.