We report the experimental observation of commensurability oscillations (COs) in 1D graphene superlattices. The widely tunable periodic potential modulation in hBN encapsulated graphene is generated via the interplay of nanopatterned few layer graphene acting as a local bottom gate and a global Si back gate. The longitudinal magneto-resistance shows pronounced COs, when the sample is tuned into the unipolar transport regime. We observe up to six CO minima, providing evidence for a long mean free path despite the potential modulation. Comparison to existing theories shows that small angle scattering is dominant in hBN/graphene/hBN heterostructures. We observe robust COs persisting to temperature exceeding T=150 K. At high temperatures, we find deviations from the predicted T-dependence, which we ascribe to electron-electron scattering.
@article{arxiv.1802.00016,
title = {Commensurability Oscillations in One-Dimensional Graphene Superlattices},
author = {Martin Drienovsky and Jonas Joachimsmeyer and Andreas Sandner and Ming-Hao Liu and Takashi Taniguchi and Kenji Watanabe and Klaus Richter and Dieter Weiss and Jonathan Eroms},
journal= {arXiv preprint arXiv:1802.00016},
year = {2018}
}
Comments
6 pages, 4 figures + Supplemental Material. Accepted by PRL