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arXiv · 1911.11385

Exciton-Polariton Topological Insulator with an Array of Magnetic Dots

Meng Sun·Dogyun Ko·D. Leykam·V. M. Kovalev·I. G. Savenko
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Abstract

Recently there have been several proposals on exciton-polariton topological insulators, most requiring strong external magnetic fields induced by bulky superconducting coils. We propose an alternate design for a polariton topological insulator, where excitons are in a proximity of an additional layer of a ferromagnetic material with a predefined magnetic moment located between the pillars of the cavity. Our design supports a variety of topological phases and transitions between Chern numbers $\pm 2$ and $\pm 1$ by varying either the magnetic moment of the ferromagnetic material or the spin-orbit coupling between different spin projections, thus enabling compact polariton devices harnessing switchable topological edge modes.

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Meng Sun, Dogyun Ko, D. Leykam, V. M. Kovalev, I. G. Savenko. 2019-11-26. Exciton-Polariton Topological Insulator with an Array of Magnetic Dots. https://doi.org/10.1103/physrevapplied.12.064028

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