Strain-Controlled Magnetocrystalline Anisotropy in Atomically Thin Ir-Stacked 1T-CrTe2

Two-dimensional(2D) ferromagnetic materials with tunablemagnetocrystallineanisotropy (MCA) hold great promise for the realization of magnetictunnel junctions combining enhanced information stability and highenergy efficiency. Here, using first-principles calculations, we proposethe utilization of an atomically thin Ir capping layer to optimizethe electronic structure and magnetic properties of a 1T-CrTe2 monolayer. The influences of the magnetized Ir capping monolayerand various strain effects on the MCA of layered 1T-CrTe2 are investigated. We demonstrate that the stacking configurationsand the type of strain play a key role in determining their MCA energy.Notably, the MCA of an Ir-capped structure increases significantlyfrom -1.773 to -4.746 meV/u.c. when the applied uniaxialtensile strain on the a-axis changes from 0 to 2%.The underlying atomic mechanism primarily originates from the strain-inducedchange of 5d orbital states derived from Ir atoms,which in turn leads to a corresponding competitive variation of thespin-orbit coupling energy between the spin-parallel and spin-flipchannels. These results not only reveal a vital scheme for interfacialengineering to control 2D ferromagnets but also provide alternativecandidates for the design of ultralow-energy memory devices.