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Title: Room-temperature single photon emitters in cubic boron nitride nanocrystals

Color centers in wide bandgap semiconductors are attracting broad attention for use as platforms for quantum technologies relying on room-temperature single-photon emission (SPE), and for nanoscale metrology applications building on the centers’ response to electric and magnetic fields. Here, we demonstrate room-temperature SPE from defects in cubic boron nitride (cBN) nanocrystals, which we unambiguously assign to the cubic phase using spectrally resolved Raman imaging. These isolated spots show photoluminescence (PL) spectra with zero-phonon lines (ZPLs) within the visible region (496–700 nm) when subject to sub-bandgap laser excitation. Second-order autocorrelation of the emitted photons reveals antibunching withg2(0) ∼ 0.2, and a decay constant of 2.75 ns that is further confirmed through fluorescence lifetime measurements. The results presented herein prove the existence of optically addressable isolated quantum emitters originating from defects in cBN, making this material an interesting platform for opto-electronic devices and quantum applications.

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Award ID(s):
1906096 1726573
Author(s) / Creator(s):
; ; ; ; ; ; ; ;
Publisher / Repository:
Optical Society of America
Date Published:
Journal Name:
Optical Materials Express
Page Range / eLocation ID:
Article No. 843
Medium: X
Sponsoring Org:
National Science Foundation
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