The presence of topologically protected edge states is usually determined by angular-resolved photoelectron spectroscopy, requiring clean surfaces and ultrahigh vacuum. Now, an all-optical technique, based on high-harmonic radiation, has been shown to detect topological phase transitions under ambient conditions.

中文翻译：

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光学传感拓扑相变

拓扑保护边缘状态的存在通常由角分辨光电子能谱确定，需要清洁的表面和超高真空。现在，一种基于高次谐波辐射的全光学技术已被证明可以检测环境条件下的拓扑相变。