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arXiv · 1904.08531

Direct Measurement of Quantum Efficiency of Single Photon Emitters in Hexagonal Boron Nitride

Niko Nikolay·Noah Mendelson·Ersan Özelci·Bernd Sontheimer·Florian Böhm·Günter Kewes·Milos Toth·Igor Aharonovich·Oliver Benson
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Abstract

Single photon emitters in two-dimensional materials are promising candidates for future generation of quantum photonic technologies. In this work, we experimentally determine the quantum efficiency (QE) of single photon emitters (SPE) in few-layer hexagonal boron nitride (hBN). We employ a metal hemisphere that is attached to the tip of an atomic force microscope to directly measure the lifetime variation of the SPEs as the tip approaches the hBN. This technique enables non-destructive, yet direct and absolute measurement of the QE of SPEs. We find that the emitters exhibit very high QEs approaching $(87 \pm 7)\,\%$ at wavelengths of $\approx\,580\,\mathrm{nm}$, which is amongst the highest QEs recorded for a solid state single photon emitter.

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Niko Nikolay, Noah Mendelson, Ersan Özelci, Bernd Sontheimer, Florian Böhm, Günter Kewes, Milos Toth, Igor Aharonovich, Oliver Benson. 2019-04-17. Direct Measurement of Quantum Efficiency of Single Photon Emitters in Hexagonal Boron Nitride. https://doi.org/10.1364/optica.6.001084

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