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arXiv · 2406.10243

RKKY interaction in helical higher-order topological insulators

Sha Jin·Jian Li·Qing-Xu Li·Jia-Ji Zhu
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Abstract

We theoretically investigate the RKKY interaction in helical higher-order topological insulators (HOTIs), revealing distinct behaviors mediated by hinge and Dirac-type bulk carriers. Our findings show that hinge-mediated interactions consist of Heisenberg, Ising, and Dzyaloshinskii-Moriya (DM) terms, exhibiting a decay with impurity spacing z and oscillations with Fermi energy {\epsilon}F . These interactions demonstrate ferromagnetic behaviors for the Heisenberg and Ising terms and alternating behavior for the DM term. In contrast, bulk-mediated interactions include Heisenberg, twisted Ising, and DM terms, with a conventional cubic oscillating decay. This study highlights the nuanced interplay between hinge and bulk RKKY interactions in HOTIs, offering insights into the design of next-generation quantum devices based on the HOTIs.

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Sha Jin, Jian Li, Qing-Xu Li, Jia-Ji Zhu. 2024-06-06. RKKY interaction in helical higher-order topological insulators. https://doi.org/10.1088/1674-1056/ad3ef9

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