Observation of topological transition in high-T$_{c}$ superconductor FeTe$_{1-x}$Se$_{x}$/SrTiO$_{3}$(001) monolayers

X. -L. Peng; Y. Li; X. -X. Wu; H. -B. Deng; X. Shi; W. -H. Fan; M. Li; Y. -B. Huang; T. Qian; P. Richard; J. -P. Hu; S. -H. Pan; H. -Q. Mao; Y. -J. Sun; H. Ding

doi:10.1103/physrevb.100.155134

arXiv · 1903.05968

Observation of topological transition in high-T$_{c}$ superconductor FeTe$_{1-x}$Se$_{x}$/SrTiO$_{3}$(001) monolayers

X. -L. Peng·Y. Li·X. -X. Wu·H. -B. Deng·X. Shi·W. -H. Fan·M. Li·Y. -B. Huang·T. Qian·P. Richard·J. -P. Hu·S. -H. Pan·H. -Q. Mao·Y. -J. Sun·H. Ding

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Abstract

Superconductors with topological surface or edge states have been intensively explored for the prospect of realizing Majorana bound states, which obey non-Abelian statistics and are crucial for topological quantum computation. The traditional routes for making topological insulator/superconductor and semiconductor/superconductor heterostructures suffer fabrication difficulties and can only work at low temperature. Here, we use angle-resolved photoemission spectroscopy to directly observe the evolution of a topological transition of band structure nearby the Fermi level in two-dimensional high-T$_{c}$ superconductor FeTe$_{1-x}$Se$_{x}$/SrTiO$_{3}$(001) monolayers, fully consistent with our theoretical calculations. Furthermore, evidence of edge states is revealed by scanning tunneling spectroscopy with assistance of theoretical calculations. Our study provides a simple and tunable platform for realizing and manipulating Majorana states at high temperature.

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X. -L. Peng, Y. Li, X. -X. Wu, H. -B. Deng, X. Shi, W. -H. Fan, M. Li, Y. -B. Huang, T. Qian, P. Richard, J. -P. Hu, S. -H. Pan, H. -Q. Mao, Y. -J. Sun, H. Ding. 2019-03-14. Observation of topological transition in high-T$_{c}$ superconductor FeTe$_{1-x}$Se$_{x}$/SrTiO$_{3}$(001) monolayers. https://doi.org/10.1103/physrevb.100.155134

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