Room-temperature ferromagnetism, half-metallicity and spin transport in monolayer CrSc2Te4-based magnetic tunnel junction devices

Abstract

The discovery of novel two-dimensional (2D) half-metallic materials with a robust ferromagnetic (FM) order and a high Curie temperature (T_c) is attractive for the advancement of next-generation spintronic devices. Here, we propose a monolayer with stable 2D intrinsic FM half-metallicity, i.e., the CrSc₂Te₄ monolayer, which was constructed by intercalating a monolayer of 1T-CrTe₂-type sandwiched between two layers of 2H-ScTe₂ monolayers. Our calculations reveal that it exhibits exceptional dynamical, thermal, and mechanical stabilities accompanied by a robust half-metallicity characterized by a wide bandgap of 1.02 eV and FM ordering with a high T_c of 326 K. Notably, these properties remain intact in almost the entire range of the biaxial strain from −5% to 5%. Furthermore, our investigations demonstrate excellent spin transport capabilities, including an outstanding spin-filtering effect, and a remarkably high tunneling magnetoresistance ratio peaking at 6087.07%. The remarkable magnetic features of the 2D CrSc₂Te₄ monolayer with room temperature FM, intrinsic half-metallicity, and 100% spin-polarization make it a promising candidate for the next-generation high-performance spintronic nanodevices as well as high-density magnetic recording and sensors.