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arXiv · 1812.02281

Selective generation and amplification of RKKY interactions by P-N interface

Shu-Hui Zhang·Jia-Ji Zhu·Wen Yang·Kai Chang
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Abstract

We propose a physical mechanism to generate and selectively amplify anisotropic Rudermann-Kittel-Kasuya-Yosida (RKKY) interactions between two local spins. The idea is to combine the deflection of the carrier velocity by a P-N interface and the locking of this velocity to the carrier spin orientation via spin-orbit coupling. We provide analytical and numerical results to demonstrate this mechanism on the surface of a topological insulator P-N junction. This work identifies the P-N interface as a second knob which, together with the carrier density, enables independent control of the strength and anisotropy of the RKKY interaction over a wide range. These findings may be relevant to scalable quantum computation and two-impurity quantum criticality.

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Shu-Hui Zhang, Jia-Ji Zhu, Wen Yang, Kai Chang. 2018-12-06. Selective generation and amplification of RKKY interactions by P-N interface. https://doi.org/10.1103/physrevb.99.195456

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