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arXiv · 2404.16520

Topological properties of finite-size heterostructures of magnetic topological insulators and superconductors

Julian Legendre·Eduárd Zsurka·Daniele Di Miceli·Llorenç Serra·Kristof Moors·Thomas L. Schmidt
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Abstract

Heterostructures of magnetic topological insulators (MTIs) and superconductors (SCs) in two-dimensional (2D) slab and one-dimensional (1D) nanoribbon geometries have been predicted to host, respectively, chiral Majorana edge states (CMESs) and Majorana bound states (MBSs). We study the topological properties of such MTI/SC heterostructures upon variation of the geometry from wide slabs to quasi-1D nanoribbon systems and as a function of the chemical potential, the magnetic doping, and the induced superconducting pairing potential. To do so, we construct effective symmetry-constrained low-energy Hamiltonians accounting for the real-space confinement. For a nanoribbon geometry with finite width and length, we observe different phases characterized by CMESs, MBSs, as well as coexisting CMESs and MBSs, as the chemical potential, the magnetic doping and/or the width are varied.

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Julian Legendre, Eduárd Zsurka, Daniele Di Miceli, Llorenç Serra, Kristof Moors, Thomas L. Schmidt. 2024-04-25. Topological properties of finite-size heterostructures of magnetic topological insulators and superconductors. https://doi.org/10.1103/physrevb.110.075426

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