论文标题
Weyl半候选材料的表面带字符MOTE $ _2 $由一步arpes理论揭示
Surface band characters of Weyl semimetal candidate material MoTe$_2$ revealed by one-step ARPES theory
论文作者
论文摘要
在T $ _D $ Crystal相中，分层的2D物质Mote $ _2 $是一个半学，从理论上讲，它具有与Weyl Fermions相对应的拓扑上的非平凡带。然而，缺乏通过角度分辨光发射光谱（ARPE）的清晰实验证据，但缺乏仔细检查基态条带结构计算与ARPES强度图之间的关系。在这里，我们通过ARPES测量，密度功能理论和一步模型ARPES计算，报告了MOTE $ _2 $（t $ _D $）的近乎Fermi-Energy带结构的研究。获得理论与实验之间的良好一致性。我们分析了表面带的轨道特征及其与ARPES极化依赖性的关系。我们发现，光极化具有主要的效果，可以通过ARPE观察到哪些条带。对于S偏振光，ARPES强度由地下Mo D轨道支配，而P偏振光揭示了主要源自TE P轨道的频带。确定可观察电子或孔口袋的合适的光极化
The layered 2D-material MoTe$_2$ in the T$_d$ crystal phase is a semimetal which has theoretically been predicted to possess topologically non-trivial bands corresponding to Weyl fermions. Clear experimental evidence by angle-resolved photoemission spectroscopy (ARPES) is, however, lacking, which calls for a careful examination of the relation between ground state band structure calculations and ARPES intensity plots. Here we report a study of the near Fermi-energy band structure of MoTe$_2$(T$_d$) by means of ARPES measurements, density functional theory, and one-step-model ARPES calculations. Good agreement between theory and experiment is obtained. We analyze the orbital character of the surface bands and its relation to the ARPES polarization dependence. We find that light polarization has a major efect on which bands can be observed by ARPES. For s-polarized light, the ARPES intensity is dominated by subsurface Mo d orbitals, while p-polarized light reveals the bands composed mainly derived from Te p orbitals. Suitable light polarization for observing either electron or hole pocket are determined
