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arXiv · 2004.05848

Topological magnetic line defects in Fe(Te,Se) high-temperature superconductors

Xianxin Wu·Jia-Xin Yin·Chao-Xing Liu·Jiangping Hu
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Abstract

Magnetic impurity chains on top of conventional superconductors are promising platforms to realize Majorana modes. Iron-based high-temperature superconductors are known in the vicinity of magnetic states due to the strong Hund's coupling in iron atoms. Here we propose that the line defects with missing Te/Se anions in Fe(Se,Te) superconductors provide the realization of intrinsic antiferromagnetic(AFM) chains with Rashba spin-orbit coupling. Against conventional wisdom, Majorana zero modes (MZMs) can be robustly generated at these AFM chain ends. These results can consistently explain the recent experimental observation of zero-energy end states in line defects of monolayer Fe(Te,Se)/SrTiO$_3$ by scanning tunneling microscopy (STM) measurements. Our research not only demonstrates an unprecedented interplay among native line defect, emergent magnetism and topological superconductivity but also explores a high-temperature platform for Majorana fermions.

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Xianxin Wu, Jia-Xin Yin, Chao-Xing Liu, Jiangping Hu. 2020-04-13. Topological magnetic line defects in Fe(Te,Se) high-temperature superconductors. https://arxiv.org/abs/2004.05848

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