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arXiv · 1308.3965

Electronic band gaps and transport properties in aperiodic bilayer graphene superlattices of Thue-Morse sequence

Changan Li·Hemeng Cheng·Ruofan Chen·Tianxing Ma·Li-Gang Wang·Yun Song·Hai-Qing Lin
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Abstract

We investigate electronic band structure and transport properties in bilayer graphene superlattices of Thue-Morse sequence. It is interesting to find that the zero-$\bar{k}$ gap center is sensitive to interlayer coupling $t'$, and the centers of all gaps shift versus $t'$ at a linear way. Extra Dirac points may emerge at $k_{y}\ne$0, and when the extra Dirac points are generated in pairs, the electronic conductance obeys a diffusive law, and the Fano factor tends to be 1/3 as the order of Thue-Morse sequence increases. Our results provide a flexible and effective way to control the transport properties in graphene.

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Changan Li, Hemeng Cheng, Ruofan Chen, Tianxing Ma, Li-Gang Wang, Yun Song, Hai-Qing Lin. 2013-10-14. Electronic band gaps and transport properties in aperiodic bilayer graphene superlattices of Thue-Morse sequence. https://doi.org/10.1063/1.4826643

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