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arXiv · 2408.03518

Large positive magnetoconductance in carbon nanoscrolls

Yu-Jie Zhong·Jia-Cheng Li·Xuan-Fu Huang·Ying-Je Lee·Ting-Zhen Chen·Jia-Ren Zhang·Angus Huang·Hsiu-Chuan Hsu·Carmine Ortix·Ching-Hao Chang
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Abstract

We theoretically demonstrate that carbon nanoscrolls -- spirally wrapped graphene layers with open endpoints -- can be characterized by a large positive magnetoconductance. We show that when a carbon nanoscroll is subject to an axial magnetic field of several Tesla, the ballistic conductance at low carrier densities of the nanoscroll has an increase of about 200%. Importantly, we find that this positive magnetoconductance is not only preserved in an imperfect nanoscroll (with disorder or mild inter-turn misalignment) but can even be enhanced in the presence of on-site disorder. We prove that the positive magnetoconductance comes about the emergence of magnetic field-induced zero energy modes, specific of rolled-up geometries. Our results establish curved graphene systems as a new material platform displaying sizable magnetoresistive phenomena.

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Yu-Jie Zhong, Jia-Cheng Li, Xuan-Fu Huang, Ying-Je Lee, Ting-Zhen Chen, Jia-Ren Zhang, Angus Huang, Hsiu-Chuan Hsu, Carmine Ortix, Ching-Hao Chang. 2024-08-07. Large positive magnetoconductance in carbon nanoscrolls. https://doi.org/10.1021/acs.nanolett.4c03694

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