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arXiv · 1011.0369

Edge stability, reconstruction, zero-energy states and magnetism in triangular graphene quantum dots with zigzag edges

Oleksandr Voznyy·Alev Devrim Güçlü·Pawel Potasz·Pawel Hawrylak
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Abstract

We present the results of ab-initio density functional theory based calculations of the stability and reconstruction of zigzag edges in triangular graphene quantum dots. We show that, while the reconstructed pentagon-heptagon zigzag edge structure is more stable in the absence of hydrogen, ideal zigzag edges are energetically favored by hydrogen passivation. Zero-energy band exists in both structures when passivated by hydrogen, however in case of pentagon-heptagon zigzag, this band is found to have stronger dispersion, leading to the loss of net magnetization.

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Oleksandr Voznyy, Alev Devrim Güçlü, Pawel Potasz, Pawel Hawrylak. 2010-11-01. Edge stability, reconstruction, zero-energy states and magnetism in triangular graphene quantum dots with zigzag edges. https://doi.org/10.1103/physrevb.83.165417

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