Dynamical signatures of point-gap Weyl semimetal
Dynamical signatures of point-gap Weyl semimetal
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DOI：
10.1103/physrevb.106.094305
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发表时间：
2021-07
影响因子：
3.7
通讯作者：
Haiping Hu;E. Zhao;W. Liu
中科院分区：
文献类型：
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作者：
Haiping Hu;E. Zhao;W. Liu
我们证明了点隙Weyl半金属的一些独特的动力学性质，这是一个三维的本征非厄米拓扑相。我们考虑一个具体的模型，其中一对Weyl点位于复能量平面的虚轴上，打开一个以拓扑不变量W_3$为特征的点间隙。这就产生了与厄米维半金属中的表面光谱和动力学响应根本不同的表面光谱和动力学响应。首先，我们预测在没有电场的情况下，电流会随时间沿磁场流动，这与手性异常驱动的电流形成鲜明对比，手性异常需要电场和磁场。其次，我们揭示了一种新型的边界-蒙皮模式在线材几何中成为局部化在线材截面的两个角。我们解释了它的起源，并展示了它在波包动力学中的实验特征。
We demonstrate a few unique dynamical properties of point-gap Weyl semimetal, an intrinsic non-Hermitian topological phase in three dimensions. We consider a concrete model where a pair of Weyl points reside on the imaginary axis of the complex energy plane, opening up a point gap characterized by a topological invariant, the three-winding number $W_3$. This gives rise to surface spectra and dynamical responses that differ fundamentally from those in Hermitian Weyl semimetals. First, we predict a time-dependent current flow along the magnetic field in the absence of an electric field, in sharp contrast to the current driven by the chiral anomaly, which requires both electric and magnetic fields. Second, we reveal a novel type of boundary-skin mode in the wire geometry which becomes localized at two corners of the wire cross section. We explain its origin and show its experimental signatures in wave-packet dynamics.