Temperature-dependent electronic structure in a higher-order topological insulator candidate EuIn2As2
Temperature-dependent electronic structure in a higher-order topological insulator candidate EuIn2As2
复制标题
DOI：
10.1103/physrevb.102.165153
复制
发表时间：
2020-10-29
影响因子：
3.7
通讯作者：
Neupane, Madhab
中科院分区：
文献类型：
--
作者：
Regmi, Sabin;Hosen, M. Mofazzel;Neupane, Madhab
高阶拓扑绝缘体（HOTIs）由于其支持沿晶体铰链的无间隙状态的新颖性而吸引了巨大的研究兴趣。尽管有几个理论预测，但晶体固体中HOTI状态的足够实验证实仍然缺乏。结果表明，拓扑与磁性的相互作用可以产生各种磁性拓扑态，包括HOTI态和轴子绝缘子态。本文采用高分辨率角分辨光电发射光谱结合第一性原理计算，系统地研究了具有低于16 K的反铁磁基态的EuIn2As2的电子结构及其在磁相变过程中的演变。反铁磁EuIn2As2被预测同时具有轴子绝缘体和HOTI态。我们直接观察了穿越费米能级的线性色散空穴带及其在磁相变中的色散变化。我们的论文指出，EuIn2As2是一种很有前途的材料，用于探索拓扑和磁性之间的相互作用。
Higher-order topological insulators (HOTIs) have enticed enormous research interests owing to their novelty in supporting gapless states along the hinges of a crystal. Despite several theoretical predictions, enough experimental confirmation of the HOTI state in crystalline solids is still lacking. It is shown that interplay between topology and magnetism can give rise to various magnetic topological states, including HOTI and axion insulator states. Here, using high-resolution angle-resolved photoemission spectroscopy combined with the first-principles calculations, we report a systematic study of the electronic structure and its evolution across the magnetic phase transition in EuIn2As2 which possesses an antiferromagnetic ground state below 16 K. Antiferromagnetic EuIn2As2 has been predicted to host both the axion insulator and the HOTI states. We directly observe the linearly dispersing holelike bands crossing the Fermi level and the change in their dispersion across the magnetic phase transition. Our paper points to EuIn2As2 as being a promising material for the exploration of interplay between topology and magnetism.