Optical conductivity of the type-II Weyl semimetal TaIrTe4
Optical conductivity of the type-II Weyl semimetal TaIrTe4
复制标题
DOI：
10.1103/physrevb.102.045201
复制
发表时间：
2020-07-06
影响因子：
3.7
通讯作者：
Akrap, Ana
中科院分区：
文献类型：
--
作者：
Le Mardele, F.;Santos-Cottin, D.;Akrap, Ana
TaIrTe 4是具有最小可能数量的外尔节点的候选外尔II型半金属的示例。四个节点被报告存在于k空间中的单个平面中。与Weyl节点相关的锥形色散的存在还有待实验证明。在这里，我们使用光学光谱作为探针的能带结构在低能量范围内。研究光学电导率使我们能够探测零动量的带内和带间跃迁。在TaIrTe 4，我们观察到一个狭窄的德鲁德贡献和带间电导率，可能是一致的倾斜线性带色散高达40毫电子伏。带间电导率使我们能够建立圆锥色散的有效参数;有效速度v = 1.1 × 10（4）m/s和倾斜γ = 0.37。的传输数据，塞贝克和霍尔系数，是定性一致的带结构中的锥形功能。定量分歧可能与TaIrTe 4的多波段性质有关。
TaIrTe4 is an example of a candidate Weyl type-II semimetal with a minimal possible number of Weyl nodes. Four nodes are reported to exist in a single plane in k space. The existence of a conical dispersion linked toWeyl nodes has yet to be shown experimentally. Here, we use optical spectroscopy as a probe of the band structure on a low-energy scale. Studying optical conductivity allows us to probe intraband and interband transitions with zero momentum. In TaIrTe4, we observe a narrow Drude contribution and an interband conductivity that may be consistent with a tilted linear band dispersion up to 40 meV. The interband conductivity allows us to establish the effective parameters of the conical dispersion; effective velocity v = 1.1 x 10(4) m/s and tilt gamma = 0.37. The transport data, Seebeck and Hall coefficients, are qualitatively consistent with conical features in the band structure. Quantitative disagreement may be linked to the multiband nature of TaIrTe4.