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arXiv · 1308.0713

Optical properties of the Hofstadter butterfly in the Moiré superlattice

Pilkyung Moon·Mikito Koshino
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Abstract

We investigate the optical absorption spectrum and the selection rule for the Hofstadter butterfly in twisted bilayer graphene under magnetic fields. We demonstrate that the absorption spectrum exhibits a self-similar recursive pattern reflecting the fractal nature of the energy spectrum. We find that the optical selection rule has a nested self-similar structure as well, and it is governed by the conservation of the total angular momentum summed over different hierarchies.

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Pilkyung Moon, Mikito Koshino. 2014-01-10. Optical properties of the Hofstadter butterfly in the Moiré superlattice. https://doi.org/10.1103/physrevb.88.241412

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