Revealing multiple classes of stable quantum emitters in hexagonal boron nitride with correlated optical and electron microscopy.
Fariah HayeeLeo YuJingyuan Linda ZhangChristopher J CiccarinoMinh NguyenAnn F MarshallIgor AharonovichJelena VučkovićPrineha NarangTony F HeinzJennifer A DionnePublished in: Nature materials (2020)
Defects in hexagonal boron nitride (hBN) exhibit high-brightness, room-temperature quantum emission, but their large spectral variability and unknown local structure challenge their technological utility. Here, we directly correlate hBN quantum emission with local strain using a combination of photoluminescence (PL), cathodoluminescence (CL) and nanobeam electron diffraction. Across 40 emitters, we observe zero phonon lines (ZPLs) in PL and CL ranging from 540 to 720 nm. CL mapping reveals that multiple defects and distinct defect species located within an optically diffraction-limited region can each contribute to the observed PL spectra. Local strain maps indicate that strain is not required to activate the emitters and is not solely responsible for the observed ZPL spectral range. Instead, at least four distinct defect classes are responsible for the observed emission range, and all four classes are stable upon both optical and electron illumination. Our results provide a foundation for future atomic-scale optical characterization of colour centres.
Keyphrases
- electron microscopy
- room temperature
- high resolution
- light emitting
- quantum dots
- molecular dynamics
- energy transfer
- high speed
- optical coherence tomography
- ionic liquid
- mass spectrometry
- monte carlo
- photodynamic therapy
- magnetic resonance imaging
- current status
- reduced graphene oxide
- high density
- gold nanoparticles
- crystal structure
- electron transfer