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arXiv · 1706.05921

Unfolding energy spectra of multi-periodicity materials

Yu-ichiro Matsushita·Hirofumi Nishi·Jun-ichi Iwata·Taichi Kosugi·Atsushi Oshiyama
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Abstract

We propose a new unfolding scheme to analyze energy spectra of complex large-scale systems which are inherently of multi-periodicity. Considering twisted bilayer graphene (tBLG) as an example, we first show that the conventional unfolding scheme in the past using a single primitive-cell representation causes serious problems in analyses of the energy spectra. We then introduce our multi-space representation scheme in the unfolding method and clarify its validity for tBLG. Velocity renormalization of Dirac electrons in tBLG is elucidated in the present unfolding scheme.

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Yu-ichiro Matsushita, Hirofumi Nishi, Jun-ichi Iwata, Taichi Kosugi, Atsushi Oshiyama. 2017-06-19. Unfolding energy spectra of multi-periodicity materials. https://doi.org/10.1103/physrevmaterials.2.010801

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