2003/05/31 by Kikuo Harigaya, Atsushi Yamashiro, Yukihiro Shimoi +8
Physics and Astronomy · #cond-mat.str-el #cond-mat.mtrl-sci #physics.chem-ph #quant-ph
paper · pdf · doi:10.1016/j.jpcs.2003.10.005
published as J. Phys. Chem. Solids 65 (2004) 123-126 · 8 pages; 6 figures; accepted for publication in J. Phys. Chem. Solids; related Web site: http://staff.aist.go.jp/k.harigaya/index_E.html
arxiv created 2003/09/26 · arxiv updated 2009/11/30
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.