Massive topological edge channels in three-dimensional topological materials induced by extreme surface anisotropy

Fengfeng Zhu; Chenqiang Hua; Xiao Wang; Lin Miao; Yixi Su; Makoto Hashimoto; Donghui Lu; Zhi-Xun Shen; Jin-Feng Jia; Yunhao Lu; Dandan Guan; Dong Qian

arXiv · 2311.14069

Massive topological edge channels in three-dimensional topological materials induced by extreme surface anisotropy

Fengfeng Zhu·Chenqiang Hua·Xiao Wang·Lin Miao·Yixi Su·Makoto Hashimoto·Donghui Lu·Zhi-Xun Shen·Jin-Feng Jia·Yunhao Lu·Dandan Guan·Dong Qian

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Abstract

A two-dimensional quantum spin Hall insulator exhibits one-dimensional gapless spin-filtered edge channels allowing for dissipationless transport of charge and spin. However, the sophisticated fabrication requirement of two-dimensional materials and the low capacity of one-dimensional channels hinder the broadening applications. We introduce a method to manipulate a three-dimensional topological material to host a large number of one-dimensional topological edge channels utilizing surface anisotropy. Taking ZrTe5 as a model system, we realize a highly anisotropic surface due to the synergistic effect of the lattice geometry and Coulomb interaction, and achieve massive one-dimensional topological edge channels -- confirmed by electronic characterization using angle-resolved photoemission spectroscopy, in combination with first-principles calculations. Our work provides a new avenue to engineer the topological properties of three-dimensional materials through nanoscale tunning of surface morphology and opens up a promising prospect for the development of low-power-consumption electronic nano devices based on one-dimensional topological edge channels.

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Fengfeng Zhu, Chenqiang Hua, Xiao Wang, Lin Miao, Yixi Su, Makoto Hashimoto, Donghui Lu, Zhi-Xun Shen, Jin-Feng Jia, Yunhao Lu, Dandan Guan, Dong Qian. 2023-11-23. Massive topological edge channels in three-dimensional topological materials induced by extreme surface anisotropy. https://arxiv.org/abs/2311.14069

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