Electron transport in folded bilayer-bilayer graphene/hexagonal boron nitride superlattices under high magnetic fields

Takuya Iwasaki; Motoi Kimata; Yoshifumi Morita; Shu Nakaharai; Yutaka Wakayama; Eiichiro Watanabe; Daiju Tsuya; Kenji Watanabe; Takashi Taniguchi; Satoshi Moriyama

arXiv · 2110.00510

Electron transport in folded bilayer-bilayer graphene/hexagonal boron nitride superlattices under high magnetic fields

Takuya Iwasaki·Motoi Kimata·Yoshifumi Morita·Shu Nakaharai·Yutaka Wakayama·Eiichiro Watanabe·Daiju Tsuya·Kenji Watanabe·Takashi Taniguchi·Satoshi Moriyama

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Abstract

Employing graphene as a template, we fabricate moir\'e superlattices by stacking bilayer or folded bilayer-bilayer graphene (BLG or fBBLG) and hexagonal boron nitride (hBN), i.e., hBN/BLG/hBN or hBN/fBBLG/hBN stacks, with a small twist angle between the graphene and one of the two hBN layers. Because of the modulation due to the hBN, higher-generation Dirac points can emerge with a narrow bandwidth and van Hove singularities. In the moir\'e superlattice devices, we can therefore access the higher-generation Dirac points by in-situ gate tuning. This study is based on our previous paper (Appl. Phys. Express 13, 035003 (2020)). Here we show more extended data by applying high magnetic fields up to ~24 T. We also comment on the temperature dependence of the resistivity and magnetoresistance with reference to the 'plain' BLG data for a comparative study.

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Takuya Iwasaki, Motoi Kimata, Yoshifumi Morita, Shu Nakaharai, Yutaka Wakayama, Eiichiro Watanabe, Daiju Tsuya, Kenji Watanabe, Takashi Taniguchi, Satoshi Moriyama. 2021-10-01. Electron transport in folded bilayer-bilayer graphene/hexagonal boron nitride superlattices under high magnetic fields. https://arxiv.org/abs/2110.00510

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