Contrasting roles of the superexchange and direct exchange interactions in the metal-insulator transitions of the 2D ferromagnetic $1T$-Fe$X_2$ ($X$=Cl, Br, I) monolayers

Hongxu Luo, Baoyang Zhou, Sai Lyu

Within the rapidly growing family of two-dimensional (2D) materials, 2D ferromagnetic (FM) materials have attracted a great deal of recent attention. The ferromagnetism in 2D FM ma…