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arXiv · 1905.09185

Impurity-induced resonant states in topological nodal-line semimetals

Tao Zhou·Wei Chen·Yi Gao·Z. D. Wang
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Abstract

Nodal-line semimetals are characterized by a kind of topologically nontrivial bulk-band crossing, giving rise to almost flat surface states. Yet, a direct evidence of the surface states is still lacking. Here we study theoretically impurity effects in topological nodal-line semimetals based on the T-matrix method. It is found that for a bulk impurity, some in-gap states may be induced near the impurity site, while the visible resonant impurity state can only exist for certain strength of the impurity potentials. For a surface impurity, robust resonant impurity states exist in a wide range of impurity potentials. Such robust resonant states stem from the topological protected weak dispersive surface states, which can be probed by scanning tunneling microscopy, providing a strong signature of the topological surface states in the nodal-line semimetals.

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Tao Zhou, Wei Chen, Yi Gao, Z. D. Wang. 2019-05-22. Impurity-induced resonant states in topological nodal-line semimetals. https://doi.org/10.1103/physrevb.100.205119

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