Tunability of the topological nodal-line semimetal phase in ZrSiX-type materials (X = S, Se, Te)
Tunability of the topological nodal-line semimetal phase in ZrSiX-type materials (X = S, Se, Te)
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DOI：
10.1103/physrevb.95.161101
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发表时间：
2017-04-03
影响因子：
3.7
通讯作者：
Neupane, Madhab
中科院分区：
文献类型：
--
作者：
Hosen, M. Mofazzel;Dimitri, Klauss;Neupane, Madhab
在ZrSiS中发现了拓扑节线(TNL)半金属相，这为该家族其他成员的研究注入了新的活力。在这里，我们用角度分辨光电子能谱和第一性原理计算研究了ZrSiX(其中X=S，Se，Te)的比较电子结构。我们的ARPES研究表明，ZrSiX材料的总体电子结构由围绕布里渊区的区域中心(Gamma)点、M点和X点的钻石形费米口袋、近椭圆形状的费米口袋和一个小的电子口袋组成。我们还观察到在ZrSiTe中沿M-Gamma-M方向有一个很小的费米面口袋，这是在两种材料中都没有的。此外，我们的理论研究表明，在这些材料体系中，通过调整硫系元素从S到Te，可以从节线相转变到无节点有隙相。我们的研究结果通过X-离子调节自旋-轨道耦合强度，直接证明了在ZrSiX材料体系中TnL相的可调性。
The discovery of a topological nodal-line (TNL) semimetal phase in ZrSiS has invigorated the study of other members of this family. Here, we present a comparative electronic structure study of ZrSiX (where X = S, Se, Te) using angle-resolved photoemission spectroscopy (ARPES) and first-principles calculations. Our ARPES studies show that the overall electronic structure of ZrSiX materials comprises the diamond-shaped Fermi pocket, the nearly elliptical-shaped Fermi pocket, and a small electron pocket encircling the zone center (Gamma) point, the M point, and the X point of the Brillouin zone, respectively. We also observe a small Fermi surface pocket along the M-Gamma-M direction in ZrSiTe, which is absent in both ZrSiS and ZrSiSe. Furthermore, our theoretical studies show a transition from nodal-line to nodeless gapped phase by tuning the chalcogenide from S to Te in these material systems. Our findings provide direct evidence for the tunability of the TNL phase in ZrSiX material systems by adjusting the spin-orbit coupling strength via the X anion.