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arXiv · 1205.2965

Magneto-orbital effect without spin-orbit interactions --- noncentrosymmetric zeolite-templated carbon structure

Takashi Koretsune·Ryotaro Arita·Hideo Aoki
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Abstract

A peculiar manifestation of orbital angular momentum is proposed for a zeolite-templated carbon system, C36H9. The structure, being a network of nanoflakes in the shape of a "pinwheel", lacks inversion symmetry. While the unit cell is large, the electronic structure obtained with a first-principles density functional theory and captured as an effective tight-binding model in terms of maximally-localized Wannier functions, exhibits an unusual feature that the valence band top comes from two chiral states having orbital magnetic momenta of $\pm 1$. The noncentrosymmetric lattice structure then makes the band dispersion asymmetric, as reminiscent of, but totally different from, spin-orbit systems. The unusual feature is predicted to imply a current-induced orbital magnetism when holes are doped.

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Takashi Koretsune, Ryotaro Arita, Hideo Aoki. 2012-05-14. Magneto-orbital effect without spin-orbit interactions --- noncentrosymmetric zeolite-templated carbon structure. https://doi.org/10.1103/physrevb.86.125207

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