We study diffusive magnetotransport in highly p-doped large area twisted bilayer graphene in 1{\deg}, 7{\deg}, 9{\deg} and 20{\deg} samples. We report weak localization in twisted bilayer graphene for the first time. All samples exhibit weak localization, from which we extract the phase coherence length and intervalley scattering lengths, and from that determine that dephasing is caused by electron-electron scattering and intervalley scattering is caused by point defects. We observe signatures of universal conductance fluctuations in the 9{\deg} sample, which has high mobility and is near the van Hove singularity. Further improvements in sample quality and applications to large area moire materials will open new avenues to observe quantum interference effects.
@article{arxiv.2511.07334,
title = {Weak localization and universal conductance fluctuations in large area twisted bilayer graphene},
author = {Spenser Talkington and Debarghya Mallick and An-Hsi Chen and Benjamin F. Mead and Seong-Jun Yang and Cheol-Joo Kim and Shaffique Adam and Liang Wu and Matthew Brahlek and Eugene J. Mele},
journal= {arXiv preprint arXiv:2511.07334},
year = {2026}
}
Comments
5+1 pages, 3+1 figures; v3 added table I, journal accepted version