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arXiv · 2302.10422

Fe$_{1+y}$Te$_{x}$Se$_{1-x}$: a delicate and tunable Majorana material

Fazhi Yang·Giao Ngoc Phan·Renjie Zhang·Jin Zhao·Jiajun Li·Zouyouwei Lu·John Schneeloch·Ruidan Zhong·Mingwei Ma·Genda Gu·Xiaoli Dong·Tian Qian·Hong Ding
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Abstract

We report the observation for the p$_{z}$ electron band and the band inversion in Fe$_{1+y}$Te$_{x}$Se$_{1-x}$ with angle-resolved photoemission spectroscopy. Furthermore, we found that excess Fe (y>0) inhibits the topological band inversion in Fe$_{1+y}$Te$_{x}$Se$_{1-x}$, which explains the absence of Majorana zero modes in previous reports for Fe$_{1+y}$Te$_{x}$Se$_{1-x}$ with excess Fe. Based on our analysis of different amounts of Te doping and excess Fe, we propose a delicate topological phase in this material. Thanks to this delicate phase, one may be able to tune the topological transition via applying lattice strain or carrier doping.

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Fazhi Yang, Giao Ngoc Phan, Renjie Zhang, Jin Zhao, Jiajun Li, Zouyouwei Lu, John Schneeloch, Ruidan Zhong, Mingwei Ma, Genda Gu, Xiaoli Dong, Tian Qian, Hong Ding. 2023-02-21. Fe$_{1+y}$Te$_{x}$Se$_{1-x}$: a delicate and tunable Majorana material. https://doi.org/10.1088/0256-307x%2F40%2F1%2F017401

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