BibTex format
@article{Dou:2018:10.1021/acs.nanolett.8b00228,
author = {Dou, Z and Morikawa, S and Cresti, A and Wang, S-W and Smith, CG and Melios, C and Kazakova, O and Watanabe, K and Taniguchi, T and Masubuchi, S and Machida, T and Connolly, MR},
doi = {10.1021/acs.nanolett.8b00228},
journal = {Nano Letters},
pages = {2530--2537},
title = {Imaging bulk and edge transport near the dirac point in graphene moiré superlattices},
url = {http://dx.doi.org/10.1021/acs.nanolett.8b00228},
volume = {18},
year = {2018}
}
RIS format (EndNote, RefMan)
TY - JOUR
AB - Van der Waals structures formed by aligning monolayer graphene with insulating layers of hexagonal boron nitride exhibit a moiré superlattice that is expected to break sublattice symmetry. Despite an energy gap of several tens of millielectronvolts opening in the Dirac spectrum, electrical resistivity remains lower than expected at low temperature and varies between devices. While subgap states are likely to play a role in this behavior, their precise nature is unclear. We present a scanning gate microscopy study of moiré superlattice devices with comparable activation energy but with different charge disorder levels. In the device with higher charge impurity (∼1010 cm–2) and lower resistivity (∼10 kΩ) at the Dirac point we observe current flow along the graphene edges. Combined with simulations, our measurements suggest that enhanced edge doping is responsible for this effect. In addition, a device with low charge impurity (∼109 cm–2) and higher resistivity (∼100 kΩ) shows subgap states in the bulk, consistent with the absence of shunting by edge currents.
AU - Dou,Z
AU - Morikawa,S
AU - Cresti,A
AU - Wang,S-W
AU - Smith,CG
AU - Melios,C
AU - Kazakova,O
AU - Watanabe,K
AU - Taniguchi,T
AU - Masubuchi,S
AU - Machida,T
AU - Connolly,MR
DO - 10.1021/acs.nanolett.8b00228
EP - 2537
PY - 2018///
SN - 1530-6984
SP - 2530
TI - Imaging bulk and edge transport near the dirac point in graphene moiré superlattices
T2 - Nano Letters
UR - http://dx.doi.org/10.1021/acs.nanolett.8b00228
UR - https://pubs.acs.org/doi/10.1021/acs.nanolett.8b00228
UR - http://hdl.handle.net/10044/1/80496
VL - 18
ER -