We report ultrafast reflectivity measurements of the dynamics of the order parameter of the charge density wave (CDW) in TbTe₃ under anisotropic strain. We observe an increase in the frequency of the amplitude mode with increasing tensile strain along the a-axis (which drives the lattice into a > c, with a and c the lattice constants), and similar behavior for tensile strain along c (c > a). This suggests that both strains stabilize the corresponding CDW order and further support the near equivalence of the CDW phases oriented in a- and c-axis, in spite of the orthorhombic space group. The results were analyzed within the time-dependent Ginzburg–Landau framework, which agrees well with the reflectivity dynamics. Our study presents an ultrafast approach to assess the stability of phases and order parameter dynamics in strained systems.

中文翻译：

---

各向异性应变下超快反射率揭示了 TbTe3 中的涌现对称性


我们报告了各向异性应变下 TbTe ₃中电荷密度波 (CDW) 有序参数动力学的超快反射率测量。我们观察到，随着沿 a 轴拉伸应变的增加（将晶格驱动为 > c，其中 a 和 c 为晶格常数），振幅模式的频率会增加，并且沿 c 的拉伸应变也有类似的行为（c > a)。这表明，尽管存在斜方空间群，两种菌株都稳定了相应的 CDW 级，并进一步支持了 a 轴和 c 轴方向的 CDW 相的接近等效性。结果在依赖于时间的金兹堡-兰道框架内进行了分析，这与反射率动态非常吻合。我们的研究提出了一种超快速方法来评估应变系统中的相位稳定性和阶次参数动力学。