Experimental observation of Weyl points
Experimental observation of Weyl points
复制标题
拓扑物质 Weyl 点的实验观察
DOI：
10.1126/science.aaa9273
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发表时间：
2015-08-07
期刊：
影响因子：
56.9
通讯作者：
Soljacic, Marin
中科院分区：
文献类型：
--
作者：
Lu, Ling;Wang, Zhiyu;Soljacic, Marin
狄拉克方程的无质量解由所谓的韦尔哈密顿量描述。韦尔方程要求粒子在所有三个维度上都具有线性色散，同时在单个动量点处双重简并。这些韦尔点是量子化贝里通量的拓扑单极子，表现出许多不寻常的特性。我们通过具有反转破坏的双螺旋光子晶体进行了角度分辨微波传输测量，理论上预测会出现韦尔点。激发体态显示两个线性色散带接触三维布里渊区中的四个孤立点，表明观察到了外尔点。这项工作为三维的各种光子拓扑现象铺平了道路。
The massless solutions to the Dirac equation are described by the so-called Weyl Hamiltonian. The Weyl equation requires a particle to have linear dispersion in all three dimensions while being doubly degenerate at a single momentum point. These Weyl points are topological monopoles of quantized Berry flux exhibiting numerous unusual properties. We performed angle-resolved microwave transmission measurements through a double-gyroid photonic crystal with inversion-breaking where Weyl points have been theoretically predicted to occur. The excited bulk states show two linear dispersion bands touching at four isolated points in the three-dimensional Brillouin zone, indicating the observation of Weyl points. This work paves the way to a variety of photonic topological phenomena in three dimensions.