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arXiv · 1511.02216

Atomic Scale Visualization of Quantum Interference on a Weyl Semimetal Surface by Scanning Tunneling Microscopy/Spectroscopy

Hao Zheng·Su-Yang Xu·Guang Bian·Cheng Guo·Guoqing Chang·Daniel S. Sanchez·Ilya Belopolski·Chi-Cheng Lee·Shin-Ming Huang·Xiao Zhang·Raman Sankar·Nasser Alidoust·Tay-Rong Chang·Fan Wu·Titus Neupert·Fangcheng Chou·Horng-Tay Jeng·Nan Yao·Arun Bansil·Shuang Jia·Hsin Lin·M. Zahid Hasan
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Abstract

Weyl semimetals may open a new era in condensed matter physics, materials science and nanotech after graphene and topological insulators. We report the first atomic scale view of the surface states of a Weyl semimetal (NbP) using scanning tunneling microscopy/spectroscopy. We observe coherent quantum interference patterns that arise from the scattering of quasiparticles near point defects on the surface. The measurements reveal the surface electronic structure both below and above the chemical potential in both real and reciprocal spaces. Moreover, the interference maps uncover the scattering processes of NbP's exotic surface states. Through comparison between experimental data and theoretical calculations, we further discover that the scattering channels are largely restricted by the orbital and/or spin texture of the surface band. The visualization of the scattering processes can help design novel transport effects and electronics on the topological surface of a Weyl semimetal.

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Hao Zheng, Su-Yang Xu, Guang Bian, Cheng Guo, Guoqing Chang, Daniel S. Sanchez, Ilya Belopolski, Chi-Cheng Lee, Shin-Ming Huang, Xiao Zhang, Raman Sankar, Nasser Alidoust, Tay-Rong Chang, Fan Wu, Titus Neupert, Fangcheng Chou, Horng-Tay Jeng, Nan Yao, Arun Bansil, Shuang Jia, Hsin Lin, M. Zahid Hasan. 2015-11-06. Atomic Scale Visualization of Quantum Interference on a Weyl Semimetal Surface by Scanning Tunneling Microscopy/Spectroscopy. https://doi.org/10.1021/acsnano.5b06807

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