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

TL;DR

This study demonstrates that CVD-grown small-angle twisted bilayer graphene can achieve high-quality, uniform moiré superlattice transport properties, offering a scalable alternative to exfoliated samples for fundamental research and future applications.

Contribution

It provides a scalable method to produce high-quality twisted bilayer graphene with uniform moiré patterns, enabling reliable transport studies and potential large-scale device fabrication.

Findings

Observation of tunable interlayer coupling regimes.

Detection of density-independent Brown-Zak oscillations.

Reduced Fermi velocity in the twisted bilayer graphene.

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.