Anomalous Shiba states in topological iron-based superconductors
Anomalous Shiba states in topological iron-based superconductors
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DOI：
10.1103/physrevb.106.l201107
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发表时间：
2022-07
影响因子：
3.7
通讯作者：
A. Ghazaryan;A. Kirmani;R. Fernandes;Pouyan Ghaemi
中科院分区：
文献类型：
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作者：
A. Ghazaryan;A. Kirmani;R. Fernandes;Pouyan Ghaemi
我们证明了铁基超导体FeSe 1 − x Te x中接近磁性杂质的鲁棒零能量模式的形成。我们发现，由杂质产生的塞曼场有利于自旋三重态轨道间配对，而不是自旋单线态轨道内配对普遍存在于散装。优选的自旋三重态配对保持时间反演对称性并且是拓扑的，因为在具有不同配对状态的区域之间的边界处出现鲁棒的、拓扑保护的零模式。此外，零模形成Kramers双峰，其对自旋极化的方向或杂质之间的分离不敏感。我们认为，我们的理论结果与最近的实验测量FeSe 1 − x Te x是一致的。本文建立了正文中讨论的奇宇称配对态的超导耦合常数g2 ±和g3 ±与广义Hubbard Kanamori哈密顿量[1-3]中dxz，dyz和pz三个轨道的现场相互作用项之间的关系：
We demonstrate the formation of robust zero energy modes close to magnetic impurities in the iron-based superconductor FeSe 1 − x Te x . We find that the Zeeman field generated by the impurity favors a spin-triplet inter-orbital pairing as opposed to the spin-singlet intra-orbital pairing prevalent in the bulk. The preferred spin-triplet pairing preserves time-reversal symmetry and is topological, as robust, topologically-protected zero modes emerge at the boundary between regions with different pairing states. Moreover, the zero modes form Kramers doublets that are insensitive to the direction of the spin polarization or to the separation between impurities. We argue that our theoretical results are consistent with recent experimental measurements on FeSe 1 − x Te x . Here we establish the relationship between the superconducting coupling constants g 2 ± and g 3 ± of the odd-parity pairing states discussed in the main text and the onsite interaction terms of a generalized Hubbard-Kanamori Hamiltonian [1–3] for the three orbitals d xz , d yz and p z :