Ultrafast control of structural and electronic properties of various quantum materials has recently sparked great interest. In particular, photoinduced switching between distinct topological phases has been considered a promising route to realize quantum computers. Here we use first-principles and effective Hamiltonian methods to show that in ZrTe₅, lattice distortions corresponding to all three types of zone-center infrared optical phonon modes can drive the system from a topological insulator to a Weyl semimetal. Thus achieved Weyl phases are robust, highly tunable, and one of the cleanest due to the proximity of the Weyl points to the Fermi level and a lack of other carriers. We also find that Berry curvature dipole moment, induced by the dynamical inversion symmetry breaking, gives rise to various nonlinear effects that oscillate with the amplitude of the phonon modes. These nonlinear effects present an ultrafast switch for controlling the Weyltronics-enabled quantum system.

最近，对各种量子材料的结构和电子特性的超快控制引起了极大的兴趣。特别是，不同拓扑相之间的光诱导切换被认为是实现量子计算机的有希望的途径。在这里，我们使用第一原理和有效的哈密顿方法来证明在 ZrTe ₅，对应于所有三种类型的区域中心红外光学声子模式的晶格畸变可以将系统从拓扑绝缘体驱动到外尔半金属。由于外尔点接近费米能级并且没有其他载流子，因此实现的外尔相是稳健的、高度可调的，并且是最干净的相之一。我们还发现，由动态反演对称性破坏引起的贝里曲率偶极矩会产生各种非线性效应，这些效应会随着声子模式的振幅而振荡。这些非线性效应为控制 Weyltronics 启用的量子系统提供了一种超快开关。