Topological corner states characteristic to second-order topological phases are observed on the surface of a solid using a scanning tunnelling microscope. This observation opens a new connection between higher-order topological physics and surface science.

中文翻译：

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受保护的角落。

使用扫描隧道显微镜在固体表面上观察到具有二阶拓扑相特征的拓扑角状态。这一观察结果开辟了高阶拓扑物理和表面科学之间的新联系。