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arXiv · 1402.4055

Quasi-1D graphene superlattices formed on high index surfaces

Chenfang Lin·Xiangqian Huang·Fen Ke·Chenhao Jin·Nai Tong·Xiuli Yin·Lin Gan·Xuefeng Guo·Ruguang Zhao·Weisheng Yang·Enge Wang·Zonghai Hu
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Abstract

We report preparation of large area quasi-1D monolayer graphene superlattices on a prototypical high index surface Cu(410)-O and characterization by Raman spectroscopy, Auger electron spectroscopy (AES), low energy electron diffraction (LEED), scanning tunneling microscopy (STM) and scanning tunneling spectroscopy (STS). The periodically stepped substrate gives a 1D modulation to graphene, forming a superlattice of the same super-periodicity. Consequently the moire pattern is also quasi-1D, with a different periodicity. Scanning tunneling spectroscopy measurements revealed new Dirac points formed at the superlattice Brillouin zone boundary as predicted by theories.

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Chenfang Lin, Xiangqian Huang, Fen Ke, Chenhao Jin, Nai Tong, Xiuli Yin, Lin Gan, Xuefeng Guo, Ruguang Zhao, Weisheng Yang, Enge Wang, Zonghai Hu. 2014-02-17. Quasi-1D graphene superlattices formed on high index surfaces. https://doi.org/10.1103/physrevb.89.085416

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