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, CrI3, in the monolayer limit. While its properties remain largely unexplored, it provides a unique material-specific platform to unveil 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, based on the results of ab initio calculations of the conductivity tensor, we study the surface electromagnetic waves localized in a CrI3-based structure. 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 and magnetic field distribution for different CrI3 layer thicknesses. We also study the bilayer structure formed by two CrI3 layers separated by a SiO2 spacer and show that the surface plasmon resonance can be obtained at the outer interface of the proposed system depending on the spacer thickness.

Magneto-optical response of chromium trihalide monolayers: chemical trends

“…27 So far, theoretical efforts have been focused on the excitonic effects on Kerr angle in monolayer CrI 3 , 28 or few-layers and bulk. 25 Others ab initio studies have described magnetic anisotropy and critical temperatures of ferromagnetic 2D materials, 29,30 localized surface waves in CrI 3 structures, 31 and structural properties. 32 Nevertheless, a theoretical study…”