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High-T _c superconductor Fe(Se,Te) monolayer: an intrinsic, scalable and electrically tunable Majorana platform.

ABSTRACT: Iron-based superconductors have been identified as a novel platform for realizing Majorana zero modes (MZMs) without heterostructures, due to their intrinsic topological properties and high-T _c superconductivity. In the two-dimensional limit, the FeTe_1-x Se _x monolayer, a topological band inversion has recently been experimentally observed. Here, we propose to create MZMs by applying an in-plane magnetic field to the FeTe_1-x Se _x monolayer and tuning the local chemical potential via electric gating. Owing to the anisotropic magnetic couplings on edges, an in-plane magnetic field drives the system into an intrinsic high-order topological superconductor phase with Majorana corner modes. Furthermore, MZMs can occur at the domain wall of chemical potentials at either one edge or certain type of tri-junction in the two-dimensional bulk. Our study not only reveals the FeTe_1-x Se _x monolayer as a promising Majorana platform with scalability and electrical tunability and within reach of contemporary experimental capability, but also provides a general principle to search for realistic realization of high-order topological superconductivity.

SUBMITTER: Wu X

PROVIDER: S-EPMC8924703 | biostudies-literature |

REPOSITORIES: biostudies-literature

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