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Theoretical study on novel electronic properties in nanographite materials

Kikuo Harigaya·Atsushi Yamashiro·Yukihiro Shimoi·Katsunori Wakabayashi·Yousuke Kobayashi·Naoki Kawatsu·Kazuyuki Takai·Hirohiko Sato·Jerome Ravier·Toshiaki Enoki·Morinobu Endo
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Abstract

Antiferromagnetism in stacked nanographite is investigated with using the Hubbard-type model. We find that the open shell electronic structure can be an origin of the decreasing magnetic moment with the decrease of the inter-graphene distance, as experiments on adsorption of molecules suggest. Next, possible charge-separated states are considered using the extended Hubbard model with nearest-neighbor interactions. The charge-polarized state could appear, when a static electric field is present in the graphene plane for example. Finally, superperiodic patterns with a long distance in a nanographene sheet observed by STM are discussed in terms of the interference of electronic wave functions with a static linear potential theoretically. In the analysis by the k-p model, the oscillation period decreases spatially in agreement with experiments.

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Kikuo Harigaya, Atsushi Yamashiro, Yukihiro Shimoi, Katsunori Wakabayashi, Yousuke Kobayashi, Naoki Kawatsu, Kazuyuki Takai, Hirohiko Sato, Jerome Ravier, Toshiaki Enoki, Morinobu Endo. 2003-09-26. Theoretical study on novel electronic properties in nanographite materials. https://doi.org/10.1016/j.jpcs.2003.10.005

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