发表机构
Hefei National Research Center for Physical Sciences at the Microscale, University of Science and Technology of China; School of Emerging Technology, University of Science and Technology of China; Hefei National Laboratory; Department of Physics, University of Science and Technology of China（中国科学技术大学微尺度物质科学国家研究中心; 中国科学技术大学前沿技术学院; 合肥国家实验室; 中国科学技术大学物理系）
机构由 AI 辅助整理，请以论文原文为准。AI 中文总结
本研究通过高阶外延稳定近化学计量比FeTe，结合光电子能谱和第一性原理计算，证实其具有非平凡Z2拓扑和狄拉克表面态，为拓扑超导研究提供了新平台。
AI 中文摘要
FeTe长期以来被视为具有平凡能带拓扑的非超导反铁磁金属，但近期在化学计量比控制方面的进展开始挑战这一观点。本文利用闪锌矿MnTe上的高阶外延技术，稳定了接近化学计量比的FeTe，其间隙Fe被强烈抑制，超导转变起始温度约为13 K。角分辨光电子能谱揭示了显著增强的准粒子相干性、清晰定义的Fe衍生空穴带，以及费米能级附近近乎二维的狄拉克锥状态。第一性原理计算识别出奇偶宇称带之间的反转，产生了非平凡的$Z_2$拓扑和与实验一致的狄拉克表面态。这些结果阐明了化学计量比超导FeTe的内在电子结构，并为非平凡能带拓扑提供了证据，使FeTe/MnTe成为探索拓扑超导性的有前景平台。
英文摘要
FeTe has long been regarded as a nonsuperconducting antiferromagnetic metal with trivial band topology, but recent advances in stoichiometry control have begun to challenge this picture. Here we use higher-order epitaxy on zinc-blende MnTe to stabilize near-stoichiometric FeTe with strongly suppressed interstitial Fe and a superconducting transition onset near 13 K. Angle-resolved photoemission spectroscopy reveals markedly enhanced quasiparticle coherence, well-defined Fe-derived hole bands, and a nearly two-dimensional Dirac-cone-like state near the Fermi level. First-principles calculations identify an inversion between odd- and even-parity bands, yielding nontrivial $Z_2$ topology and a Dirac surface state consistent with experiment. These results elucidate the intrinsic electronic structure of stoichiometric superconducting FeTe and provide evidence for nontrivial band topology, positioning FeTe/MnTe as a promising platform for exploring topological superconductivity.
Comments7 pages, 4 figures, 1 table
