The reflection point is different from the incident point on the interface between two Weyl semimetals, and a spatial shift happens during the reflection. The reflection shift vector as a function of in-plane wave vector shows vortex structures in the incident pocket (the projection of the isoenergy surface on the junction interface) and on the pocket edge. We propose a topological quantity, which is defined by the contour integration of reflection shift along the pocket edge and is proven to be the number of edge vortices as well as that of the interface Fermi arcs connected to the pocket. Every vortex is an interface particle loaded with unit topological charge and the distribution of these topological particles reflects the internal structure of the incident pocket under the influence of the transmitted medium.

中文翻译：

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反射偏移揭示的 Weyl 半金属界面拓扑


反射点与两种 Weyl 半金属之间界面上的入射点不同，反射过程中会发生空间偏移。作为面内波矢的函数的反射偏移矢量显示了入射腔（等能表面在结界面上的投影）和腔边缘的涡流结构。我们提出了一个拓扑量，它由沿腔边缘的反射偏移的轮廓积分定义，并被证明是边缘涡流的数量以及连接到腔的界面费米弧的数量。每个涡旋都是一个载有单位拓扑电荷的界面粒子，这些拓扑粒子的分布反映了在透射介质影响下的入射腔的内部结构。