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arXiv · 1006.0712

Charged defects in graphene and the ionicity of hexagonal boron nitride in direct images

Jannik C. Meyer·Simon Kurasch·Hye Jin Park·Viera Skakalova·Daniela Künzel·Axel Groß·Andrey Chuvilin·Gerardo Algara-Siller·Siegmar Roth·Takayuki Iwasaki·Ulrich Starke·Jürgen Smet·Ute Kaiser
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Abstract

We report on the detection and charge distribution analysis for nitrogen substitutional dopants in single layer graphene membranes by aberration-corrected high-resolution transmission electron microscopy (HRTEM). Further, we show that the ionicity of single-layer hexagonal boron nitride can be confirmed from direct images. For the first time, we demonstrate by a combination of HRTEM experiments and first-principles electronic structure calculations that adjustments to the atomic potentials due to chemical bonding can be discerned in HRTEM images. Our experiments open a way to discern electronic configurations in point defects or other non-periodic arrangements or nanoscale objects that can not be analyzed in an electron or x-ray diffraction experiment.

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Jannik C. Meyer, Simon Kurasch, Hye Jin Park, Viera Skakalova, Daniela Künzel, Axel Groß, Andrey Chuvilin, Gerardo Algara-Siller, Siegmar Roth, Takayuki Iwasaki, Ulrich Starke, Jürgen Smet, Ute Kaiser. 2010-06-04. Charged defects in graphene and the ionicity of hexagonal boron nitride in direct images. https://arxiv.org/abs/1006.0712

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