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Large bandgap of pressurized trilayer graphene.

ABSTRACT: Graphene-based nanodevices have been developed rapidly and are now considered a strong contender for postsilicon electronics. However, one challenge facing graphene-based transistors is opening a sizable bandgap in graphene. The largest bandgap achieved so far is several hundred meV in bilayer graphene, but this value is still far below the threshold for practical applications. Through in situ electrical measurements, we observed a semiconducting character in compressed trilayer graphene by tuning the interlayer interaction with pressure. The optical absorption measurements demonstrate that an intrinsic bandgap of 2.5 ± 0.3 eV could be achieved in such a semiconducting state, and once opened could be preserved to a few GPa. The realization of wide bandgap in compressed trilayer graphene offers opportunities in carbon-based electronic devices.

SUBMITTER: Ke F

PROVIDER: S-EPMC6511052 | biostudies-literature | 2019 May

REPOSITORIES: biostudies-literature

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Large bandgap of pressurized trilayer graphene.

Ke Feng F Chen Yabin Y Yin Ketao K Yan Jiejuan J Zhang Hengzhong H Liu Zhenxian Z Tse John S JS Wu Junqiao J Mao Ho-Kwang HK Chen Bin B

Proceedings of the National Academy of Sciences of the United States of America 20190419 19

Graphene-based nanodevices have been developed rapidly and are now considered a strong contender for postsilicon electronics. However, one challenge facing graphene-based transistors is opening a sizable bandgap in graphene. The largest bandgap achieved so far is several hundred meV in bilayer graphene, but this value is still far below the threshold for practical applications. Through in situ electrical measurements, we observed a semiconducting character in compressed trilayer graphene by tuni ...[more]

PMID: 31004055

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