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arXiv · 1811.09295

In-gap states of magnetic impurity in quantum spin Hall insulator proximitized to a superconductor

Szczepan Głodzik·Tadeusz Domański
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Abstract

We study in-gap states of a single magnetic impurity embedded in a honeycomb monolayer which is deposited on superconducting substrate. The intrinsic spin-orbit coupling induces the quantum spin Hall insulating (QSHI) phase gapped around the Fermi energy. Under such circumstances we consider the emergence of Shiba-like bound states driven by the superconducting proximity effect. We investigate their topography, spin-polarization and signatures of the quantum phase transition manifested by reversal of the local currents circulating around the magnetic impurity. These phenomena might be important for more exotic in-gap quasiparticles in such complex nanostructures as magnetic nanowires or islands, where the spin-orbit interaction along with the proximity induced electron pairing give rise to topological phases hosting the protected boundary modes.

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Szczepan Głodzik, Tadeusz Domański. 2018-11-22. In-gap states of magnetic impurity in quantum spin Hall insulator proximitized to a superconductor. https://doi.org/10.1088/1361-648x/ab786d

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