Intrinsic room-temperature ferromagnetic semiconductor InCrTe3 monolayers with large magnetic anisotropy and large piezoelectricity

Abstract

A tremendous amount of research is currently focused on two-dimensional (2D) magnetic semiconductors because of their remarkable physical properties and diverse applications. However, their applications are highly limited by the low Curie temperature (TC). Based on first-principles calculations and Monte Carlo simulations, we demonstrate that 2D InCrTe3 monolayers are ideal candidates for next-generation spintronics applications. We show that 2D InCrTe3 monolayers have thermodynamical and mechanical stability. The magnetic couplings between Cr atoms are strong ferromagnetic (FM) interactions. 2D InCrTe3 monolayers have robust FM semiconducting behavior with a bandgap of ∼0.67 eV, adequate TC (higher than ∼300 K), and a giant out-of-plane magnetic anisotropy energy (MAE) of ∼1.4 meV/Cr. Moreover, the low symmetry C3v point group leads to large in-plane piezoelectric coefficients d11 (larger than 4.8 pm/V) and out-of-plane piezoelectric coefficients d31 (larger than 0.39 pm/V), which are higher than many Janus transition metal dichalcogenides. The theoretical predictions of high TC, large MAE, and piezoelectricity in 2D InCrTe3 monolayers suggest that they have great potential for applications in spintronics, nano-sized sensors, and electromechanics.