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arXiv · 1909.13841

Localized surface electromagnetic waves in CrI$_3$-based magnetophotonic structures

Abstract

Resulting from strong magnetic anisotropy two-dimensional ferromagnetism was recently shown to be stabilized in chromium triiodide, CrI$_3$, in the monolayer limit. While its properties remain largely unexplored, it provides a unique material-specific platform to unveil its electromagnetic properties associated with coupling of modes. Indeed, trigonal symmetry in the presence of out-of-plane magnetization results in a non-trivial structure of the conductivity tensor, including the off-diagonal terms. In this paper, we study the surface electromagnetic waves localized in a CrI$_3$-based structure using the results of {\it ab initio} calculations for the CrI$_3$ conductivity tensor. In particular, we provide an estimate for the critical angle corresponding to the surface plasmon polariton generation in the Kretschmann-Raether configuration by a detailed investigation of reflectance spectrum as well as the magnetic field distribution for different CrI$_3$ layer thicknesses. We also study the bilayer structure formed by two CrI$_3$ layers separated by a SiO$_2$ spacer and show that the surface plasmon resonance can be achieved at the interface between CrI$_3$ and air depending on the spacer thickness.

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BibTeXRIS

Anastasiia A. Pervishko, Dmitry Yudin, Vijay Kumar Gudelli, Anna Delin, Olle Eriksson, Guang-Yu Guo. 2019-09-30. Localized surface electromagnetic waves in CrI$_3$-based magnetophotonic structures. https://doi.org/10.1364/oe.394113

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