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arXiv 2312.09487cond-mat.mes-hallcond-mat.mtrl-sciphysics.app-phquant-ph
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α-Bi₄Br₄ 中拓扑铰链模式的输运响应

Transport response of topological hinge modes in $α$-Bi$_4$Br$_4$

Md Shafayat Hossain, Qi Zhang, Zhiwei Wang, Nikhil Dhale, Wenhao Liu, Maksim Litskevich, Brian Casas, Nana Shumiya, Jia-Xin Yin, Tyler A. Cochran, Yongkai Li, Y… 展开作者

Md Shafayat Hossain, Qi Zhang, Zhiwei Wang, Nikhil Dhale, Wenhao Liu, Maksim Litskevich, Brian Casas, Nana Shumiya, Jia-Xin Yin, Tyler A. Cochran, Yongkai Li, Yu-Xiao Jiang, Ying Yang, Guangming Cheng, Zi-Jia Cheng, Xian P. Yang, Nan Yao, Titus Neupert, Luis Balicas, Yugui Yao, Bing Lv, M. Zahid Hasan

AI总结:

本文首次在层状拓扑绝缘体 α-Bi₄Br₄ 中观测到拓扑铰链态的量子输运,通过 h/e 周期 Aharonov-Bohm 振荡证明电子沿铰链的相位相干环行,并验证其拓扑保护鲁棒性,为高效量子电子器件发展提供直接依据。

摘要:

电子拓扑相因其独特性质而闻名,其中导电表面态存在于绝缘三维体态的边界上。虽然表面态的输运响应已被广泛研究,但拓扑铰链模式的响应仍不明确。在此,我们研究了一种层状拓扑绝缘体 α-Bi₄Br₄,并首次提供了存在于绝缘体态和表面能隙内的无隙拓扑铰链态中量子输运的证据。我们的磁阻测量揭示了明显的 h/e 周期(其中 h 表示普朗克常数,e 表示电子电荷)Aharonov-Bohm 振荡。观测到的周期性直接反映了相位相干电子传播所包围的面积,与样品铰链所包围的面积相匹配,为电子绕铰链环行的量子干涉提供了有力证据。值得注意的是,h/e 振荡随磁场方向的变化而演化,遵循由拓扑和对称性所允许的沿铰链模式的干涉路径,并且与根据我们的扫描隧道显微镜图像确定的铰链模式位置一致。引人注目的是,这种拓扑绝缘体中量子输运的演示可以通过薄片几何结构实现,并且我们表明即使在升高温度下它仍然保持鲁棒性。我们的发现共同揭示了具有拓扑性质和量子相干性的拓扑铰链模式的量子输运响应,可直接应用于高效量子电子器件的开发。

英文摘要:

Electronic topological phases are renowned for their unique properties, where conducting surface states exist on the boundary of an insulating three-dimensional bulk. While the transport response of the surface states has been extensively studied, the response of the topological hinge modes remains elusive. Here, we investigate a layered topological insulator $α$-Bi$_4$Br$_4$, and provide the first evidence for quantum transport in gapless topological hinge states existing within the insulating bulk and surface energy gaps. Our magnetoresistance measurements reveal pronounced h/e periodic (where h denotes Planck's constant and e represents the electron charge) Aharonov-Bohm oscillation. The observed periodicity, which directly reflects the enclosed area of phase-coherent electron propagation, matches the area enclosed by the sample hinges, providing compelling evidence for the quantum interference of electrons circumnavigating around the hinges. Notably, the h/e oscillations evolve as a function of magnetic field orientation, following the interference paths along the hinge modes that are allowed by topology and symmetry, and in agreement with the locations of the hinge modes according to our scanning tunneling microscopy images. Remarkably, this demonstration of quantum transport in a topological insulator can be achieved using a flake geometry and we show that it remains robust even at elevated temperatures. Our findings collectively reveal the quantum transport response of topological hinge modes with both topological nature and quantum coherence, which can be directly applied to the development of efficient quantum electronic devices.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

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