Raman spectroscopy measurement of bilayer graphene's twist angle to boron nitride

Journal Article · Mon Jul 20 04:00:00 EDT 2015 · Applied Physics Letters

DOI:https://doi.org/10.1063/1.4926918· OSTI ID:22486353

Cheng, Bin; Wang, Peng; Pan, Cheng; Miao, Tengfei; Wu, Yong; Lau, C. N.; Taniguchi, T.; Watanabe, K. ^[1]

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1. Advanced Materials Laboratory, National Institute for Materials Science, Tsukuba, Ibaraki 305-0044 (Japan)

When graphene is placed on hexagonal boron nitride with a twist angle, new properties develop due to the resulting moiré superlattice. Here, we report a method using Raman spectroscopy to make rapid, non-destructive measurements of the twist angle between bilayer graphene and hexagonal boron nitride. The lattice orientation is determined by using flakes with both bilayer and monolayer regions, and using the known Raman signature for the monolayer to measure the twist angle of the entire flake. The widths of the second order Raman peaks are found to vary linearly in the superlattice period and are used to determine the twist angle. The results are confirmed by using transport measurements to infer the superlattice period by the charge density required to reach the secondary resistance peaks. Small twist angles are also found to produce a significant modification of the first order Raman G band peak.

• OSTI ID: 22486353
• Journal Information: Applied Physics Letters, Journal Name: Applied Physics Letters Journal Issue: 3 Vol. 107; ISSN APPLAB; ISSN 0003-6951
• Country of Publication: United States
• Language: English

Related Subjects

71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
75 CONDENSED MATTER PHYSICS
SUPERCONDUCTIVITY AND SUPERFLUIDITY
BORON NITRIDES
CHARGE DENSITY
GRAPHENE
LAYERS
ORIENTATION
PEAKS
RAMAN SPECTROSCOPY
SUPERLATTICES