Katsunori Wakabayashi

TL;DR: In this article, the electronic states of graphite ribbons with edges of two typical shapes, armchair and zigzag, were studied by performing tight binding band calculations, and it was shown that the graphite ribbon showed striking contrast in the electronic state depending on the edge shape.

TL;DR: In this paper, the magnetic properties of ribbon-shaped nanographite systems with zigzag and armchair edges in a magnetic field were investigated by using a tight-binding model.

TL;DR: This review investigates nanoscale effects on the physical properties of graphene nanoribbons and clarify the role of edge boundaries, and provides analytical solutions for electronic dispersion and the corresponding wavefunction in graphene nan oribbons with their detailed derivation using wave mechanics based on the tight-binding model.

TL;DR: A two-dimensional lattice model that exhibits a nontrivial topological phase in the absence of the Berry curvature, whose integration over the momentum space, the so-called 2D Zak phase, yields a fractional wave polarization in each direction.

TL;DR: In this paper, a photonic crystal nanocavity based on a topological corner state, supported at a 90-degangled rim of a two-dimensional photonic lattice, is reported, where a combination of the bulk edge and edge-corner correspondences guarantees the presence of the higher-order topological state in a hierarchical manner.