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arXiv · 2203.15422

Moir\'e-Induced Transport in CVD-Based Small-Angle Twisted Bilayer Graphene

Giulia Piccinini·Vaidotas Mišeikis·Pietro Novelli·Kenji Watanabe·Takashi Taniguchi·Marco Polini·Camilla Coletti·Sergio Pezzini
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Abstract

To realize the applicative potential of 2D twistronic devices, scalable synthesis and assembly techniques need to meet stringent requirements in terms of interface cleanness and twist-angle homogeneity. Here, we show that small-angle twisted bilayer graphene assembled from separated CVD-grown graphene single-crystals can ensure high-quality transport properties, determined by a device-scale-uniform moire\'e potential. Via low-temperature dual-gated magnetotransport, we demonstrate the hallmarks of a $2.4^\circ$ -twisted superlattice, including tunable regimes of interlayer coupling, reduced Fermi velocity, large interlayer capacitance, and density-independent Brown-Zak oscillations. The observation of these moir\'e-induced electrical transport features establishes CVD-based twisted bilayer graphene as an alternative to 'tear-and-stack' exfoliated flakes for fundamental studies, while serving as a proof-of-concept for future large-scale assembly.

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Giulia Piccinini, Vaidotas Mišeikis, Pietro Novelli, Kenji Watanabe, Takashi Taniguchi, Marco Polini, Camilla Coletti, Sergio Pezzini. 2022-03-29. Moir\'e-Induced Transport in CVD-Based Small-Angle Twisted Bilayer Graphene. https://doi.org/10.1021/acs.nanolett.2c01114

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