Transition between strong and weak topological insulator in ZrTe(5) and HfTe(5).
Transition between strong and weak topological insulator in ZrTe(5) and HfTe(5).
复制标题
ZrTe5 和 HfTe5 中强拓扑绝缘体和弱拓扑绝缘体之间的过渡
DOI：
10.1038/srep45667
复制
发表时间：
2017-04-04
影响因子：
4.6
通讯作者：
Zhou J
中科院分区：
文献类型：
--
作者：
Fan Z;Liang QF;Chen YB;Yao SH;Zhou J
ZrTe 5和HfTe 5作为拓扑绝缘体的理论预测，近年来引起了人们越来越多的关注。然而，随后的作品显示出许多矛盾的拓扑性质。到目前为止，在不同的实验中已经观察到三种可能的相，即强TI，弱TI和Dirac半金属。从本质上讲，ZrTe5或HfTe5是否具有带隙仍然是一个问题。在这里，我们提出了详细的第一性原理计算的电子和拓扑性质的ZrTe 5和HfTe 5的不同体积，并清楚地证明了拓扑相变从一个强TI，经过一个中间的狄拉克半金属状态，然后到一个弱TI时，晶体膨胀。我们的工作可能会对这些不同的实验结果给出统一的解释，并为进一步的实验提供重要的线索，以阐明这些材料的拓扑性质。
ZrTe5 and HfTe5 have attracted increasingly attention recently since the theoretical prediction of being topological insulators (TIs). However, subsequent works show many contradictions about their topolog-ical nature. Three possible phases, i.e. strong TI, weak TI, and Dirac semi-metal, have been observed in different experiments until now. Essentially whether ZrTe5 or HfTe5 has a band gap or not is still a question. Here, we present detailed first-principles calculations on the electronic and topological prop-erties of ZrTe5 and HfTe5 on variant volumes and clearly demonstrate the topological phase transition from a strong TI, going through an intermediate Dirac semi-metal state, then to a weak TI when the crystal expands. Our work might give a unified explain about the divergent experimental results and propose the crucial clue to further experiments to elucidate the topological nature of these materials.