Observation of topological surface states in the high-temperature superconductor MgB2
Observation of topological surface states in the high-temperature superconductor MgB2
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DOI：
10.1103/physrevb.100.184511
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发表时间：
2018-05
影响因子：
3.7
通讯作者：
Xiaoqing Zhou;Kyle N. Gordon;Kyung-Hwan Jin;Haoxiang Li;Dushyant Narayan;Hengdi Zhao;Hao Zheng;Huaqing Huang;G. Cao;Nikolai Zhigadlo;Feng Liu;D. Dessau
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文献类型：
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作者：
Xiaoqing Zhou;Kyle N. Gordon;Kyung-Hwan Jin;Haoxiang Li;Dushyant Narayan;Hengdi Zhao;Hao Zheng;Huaqing Huang;G. Cao;Nikolai Zhigadlo;Feng Liu;D. Dessau
迄今为止已知的大多数拓扑超导体都存在低转变温度（Tc）和/或对无序和掺杂水平的高脆弱性，这阻碍了这一有前途的领域的进展。在这里，利用角分辨光谱学测量和密度功能理论计算的结合，我们证明了在Tc=39 K BCS超导体MgB2的[010]面上存在一种拓扑狄拉克节点线表面态。这种表面态应该对无序和无意的掺杂变化具有高度的容忍度，并且有望通过与该状态密切相关的体超导体的邻近效应实现超导。这将代表高温拓扑超导的一种形式。
Most topological superconductors known to date suffer from low transition temperatures (Tc) and/or high fragility to disorder and dopant levels, which is hampering the progress in this promising field. Here, utilizing a combination of angle-resolved photoemission spectroscopy measurements and density-functional theory calculations, we show the presence of a type of topological Dirac nodal line surface state on the [010] faces of the Tc=39 K BCS superconductor MgB2. This surface state should be highly tolerant against disorder and inadvertent doping variations and is expected to go superconducting via the proximity effect to the bulk superconductor that this state is intimately connected to. This would represent a form of high-temperature topological superconductivity.