论文标题
从拓扑上的边缘状态中识别单层FESE中的$ S $ - 波配对对称性
Identifying $s$-wave pairing symmetry in single-layer FeSe from topologically trivial edge states
论文作者
论文摘要
确定SRTIO $ _3 $上单层FESE的配对对称性是了解增强配对机制的关键。此外，它指导探索具有高过渡温度的新超导体（$ t_ \ mathrm {c} $）。尽管做出了巨大的努力，但对称性是否是保存符号的$ S $还是签名更改的$ S _ {\ pm} $ - wave仍然存在争议。在这里，我们从拓扑角度研究了单层FESE的配对对称性。使用低温扫描隧道显微镜/光谱法，我们在单层FESE的孤立边缘和角落有系统地表征了超导状态。在边缘和角落收集的隧道光谱分别表现出完整的间隙和大幅度的凹陷，这表明缺乏拓扑上的非平凡边缘/角模式。根据理论计算，这些光谱特征是签名$ s $波配对的有力证据。
Determining the pairing symmetry of single-layer FeSe on SrTiO$_3$ is the key to understanding the enhanced pairing mechanism; furthermore, it guides exploring new superconductors with high transition temperatures ($T_\mathrm{c}$). Despite significant efforts, it remains controversial whether the symmetry is the sign-preserving $s$- or the sign-changed $s_{\pm}$-wave. Here, we investigate the pairing symmetry of single-layer FeSe from a topological point of view. Using low-temperature scanning tunneling microscopy/spectroscopy, we have systematically characterized the superconducting states at isolated edges and corners of single-layer FeSe. The tunneling spectra collected at edges and corners exhibit full gap and substantial dip, respectively, demonstrating the absence of topologically non-trivial edge/corner modes. According to the theoretical calculation, these spectroscopic features are strong evidence for the sign-preserving $s$-wave pairing.
