论文标题
拓扑绝缘子中电子能量损失光谱的轴承MIE理论
Axion Mie Theory of Electron Energy Loss Spectroscopy in Topological Insulators
论文作者
论文摘要
物质的电子拓扑状态表现出对电磁场的新型反应。例如，强拓扑绝缘子的响应的特征是电磁拉格朗日中所谓的轴突项，最终是由于存在拓扑表面状态。在这里，我们开发了用于球形颗粒的电磁响应的轴突MIE理论，包括任意磁场，即电荷和电流分布。我们得出了轴突诱导的横向磁和横向电气模式的混合，这些模式可通过实验检测到通过磁场向量的小诱导旋转。我们的结果扩展了以前对问题的分析。我们的主要重点是拓扑绝缘体中电子能量损失光谱的实验相关问题，迄今为止，该技术尚未用于检测这些材料中的轴突电磁反应。
Electronic topological states of matter exhibit novel types of responses to electromagnetic fields. The response of strong topological insulators, for instance, is characterized by a so-called axion term in the electromagnetic Lagrangian which is ultimately due to the presence of topological surface states. Here we develop the axion Mie theory for the electromagnetic response of spherical particles including arbitrary sources of fields, i.e., charge and current distributions. We derive an axion induced mixing of transverse magnetic and transverse electric modes which are experimentally detectable through small induced rotations of the field vectors. Our results extend upon previous analyses of the problem. Our main focus is on the experimentally relevant problem of electron energy loss spectroscopy in topological insulators, a technique that has so far not yet been used to detect the axion electromagnetic response in these materials.
