论文标题
X射线圆二色性与轨道磁化
X-ray circular dichroism versus orbital magnetization
论文作者
论文摘要
X射线磁圆二色性（XMCD）总规则产生了一种非常有用的地面状态，可观察到，它提供了给定材料中自发时间反转对称性破坏（T破裂）的定量度量。在一般情况下，我在这里得出了其在频段结构理论中的明确表达：琐碎的绝缘子，拓扑绝缘子和金属。轨道磁化强度提供了电子接地状态下T破裂的不同度量。两个可观察的物品属于“几何”可观察的类别。两者都是局部的，并且在坐标空间中接受了“密度”。在这两个中，都可以包括/排除选定的频段组，以获取有关T-Breaking材料的特定于元素的信息。只有在孤立的平面频带的情况下，对两个可观察物的贡献一致。最后，我提供了相应的几何公式，以一个不同的希尔伯特空间和多体相互作用的系统。
The x-ray magnetic circular dichroism (XMCD) sum rule yields an extremely useful ground-state observable, which provides a quantitative measure of spontaneous time-reversal symmetry breaking (T-breaking) in a given material. I derive here its explicit expression within band-structure theory, in the general case: trivial insulators, topological insulators, and metals. Orbital magnetization provides a different measure of T-breaking in the electronic ground state. The two observables belong to the class of "geometrical" observables; both are local and admit a "density" in coordinate space. In both of them one could include/exclude selected groups of bands, in order to acquire element-specific information about the T-breaking material. Only in the case of an isolated flat band the contributions to the two observables coincide. Finally, I provide the corresponding geometrical formula-in a different Hilbert space-for a many-body interacting system.
