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arXiv · 2110.14352

Planar magnetic texture on the surface of a topological insulator

Zhaochen Liu·Jing Wang·Congjun Wu
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Abstract

We study the planar magnetic textures in an insulating magnetic film coupled to the Dirac surface state of a topological insulator. It is shown that the radial vortex with winding number $w=\pm1$ leads to the confinement of Dirac states, where an exact mapping to the Schr\"{o}dinger equation of a two-dimensional hydrogen atom is found. The fully spin polarized zero energy bound state resembles the zeroth Landau level of Dirac electrons in a uniform out-of-plane magnetic field. Interestingly, when the hybrid system is proximity coupled to an $s$-wave superconductor, the existence of Majorana zero modes at Abrikosov vortex depends only on the relative value of the magnetic exchange coupling and the pairing strength. We conclude with a brief discussion on the physical realization with such magnetic textures.

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Zhaochen Liu, Jing Wang, Congjun Wu. 2021-10-27. Planar magnetic texture on the surface of a topological insulator. https://doi.org/10.1103/physrevb.106.035134

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