TY - JOUR
T1 - Origin of nonlinear current-voltage curves for suspended zigzag edge graphene nanoribbon
AU - Liu, Chunmeng
AU - Zhang, Jiaqi
AU - Muruganathan, Manoharan
AU - Mizuta, Hiroshi
AU - Oshima, Yoshifumi
AU - Zhang, Xiaobin
N1 - Funding Information:
The authors thank Prof. Akabori for supporting the fabrication of the GNR devices, Ms. Mizutani and Mr. Okubo for preliminary work in 2016–2018 and Prof. Sannomiya for using R005 in Tokyo Institute of Technology. The authors gratefully acknowledge the use of the facilities in the Center for Nano Materials and Technology of the Japan Advanced Institute of Science and Technology. C. Liu also thanks the China Scholarship Council under No.201808050001. X. Zhang would like to thank the supports from the Sasakawa Scientific Research Grant of The Japan Science Society, the Research Grants from the Izumi Science Foundation and the Iketani Science Foundation.
Funding Information:
The authors thank Prof. Akabori for supporting the fabrication of the GNR devices, Ms. Mizutani and Mr. Okubo for preliminary work in 2016–2018 and Prof. Sannomiya for using R005 in Tokyo Institute of Technology. The authors gratefully acknowledge the use of the facilities in the Center for Nano Materials and Technology of the Japan Advanced Institute of Science and Technology. C. Liu also thanks the China Scholarship Council under No.201808050001. X. Zhang would like to thank the supports from the Sasakawa Scientific Research Grant of The Japan Science Society , the Research Grants from the Izumi Science Foundation and the Iketani Science Foundation .
Publisher Copyright:
© 2020 Elsevier Ltd
PY - 2020/9/15
Y1 - 2020/9/15
N2 - The structure-dependent electronic properties of suspended graphene nanoribbon (GNR) have still been important issues. However, these properties have been rarely investigated experimentally due to technical difficulties to produce high-quality suspended GNRs and the identification of atomic structures. Here, we report the electronic properties of suspended GNRs by in situ transmission electron microscopy observations to simultaneously obtain the structural information while measuring the current-voltage (I-V) curves. The suspended GNRs could be obtained by convergent electron beam nanosculpting after careful cleaning by current annealing. The I-V curves were measured for GNRs with a mixture of both zigzag and armchair edges (MGNR) with widths of 3.7 to 1.9 nm and also zigzag edge GNRs (ZGNR) with widths of 1.7 to 1.2 nm. The I-V curves for the ZGNRs were different from those of the MGNRs, as follows. (1) The ZGNRs showed a sharp increase at the threshold voltage in differential conductance-voltage curves. (2) The band gaps measured for ZGNRs were smaller than the band gaps calculated using the GW approximation. (3) The threshold voltage increased with the GNR length. These findings support magnetic-insulator and nonmagnetic-metal nonequilibrium phase transitions as theoretically predicted. Narrow and short ZGNR represents the potential for further nanosized switching devices.
AB - The structure-dependent electronic properties of suspended graphene nanoribbon (GNR) have still been important issues. However, these properties have been rarely investigated experimentally due to technical difficulties to produce high-quality suspended GNRs and the identification of atomic structures. Here, we report the electronic properties of suspended GNRs by in situ transmission electron microscopy observations to simultaneously obtain the structural information while measuring the current-voltage (I-V) curves. The suspended GNRs could be obtained by convergent electron beam nanosculpting after careful cleaning by current annealing. The I-V curves were measured for GNRs with a mixture of both zigzag and armchair edges (MGNR) with widths of 3.7 to 1.9 nm and also zigzag edge GNRs (ZGNR) with widths of 1.7 to 1.2 nm. The I-V curves for the ZGNRs were different from those of the MGNRs, as follows. (1) The ZGNRs showed a sharp increase at the threshold voltage in differential conductance-voltage curves. (2) The band gaps measured for ZGNRs were smaller than the band gaps calculated using the GW approximation. (3) The threshold voltage increased with the GNR length. These findings support magnetic-insulator and nonmagnetic-metal nonequilibrium phase transitions as theoretically predicted. Narrow and short ZGNR represents the potential for further nanosized switching devices.
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U2 - 10.1016/j.carbon.2020.05.010
DO - 10.1016/j.carbon.2020.05.010
M3 - Article
AN - SCOPUS:85084675148
SN - 0008-6223
VL - 165
SP - 476
EP - 483
JO - Carbon
JF - Carbon
ER -