Modulating Curie Temperature and Magnetic Anisotropy in Nanoscale-Layered Cr2Te3 Films: Implications for Room-Temperature Spintronics

Abstract

Nanoscale-layered ferromagnets have demonstrated fascinating two-dimensional magnetism down to atomic layers, providing a peculiar playground of spin orders for investigating fundamental physics and spintronic applications. However, the strategy for growing films with designed magnetic properties is not well established yet. Herein, we present a versatile method to control the Curie temperature (T-C) and magnetic anisotropy during the growth of ultrathin Cr2Te3 films. We demonstrate an increase of the TC from 165 to 310 K in sync with magnetic anisotropy switching from an out-of-plane orientation to an in-plane one, respectively, via controlling the Te source flux during film growth, leading to different c-lattice parameters while preserving the stoichiometries and thicknesses of the films. We attributed this modulation of magnetic anisotropy to the switching of the orbital magnetic moment, using X-ray magnetic circular dichroism analysis. We also inferred that different c-lattice constants might be responsible for the magnetic anisotropy change, supported by theoretical calculations. These findings emphasize the potential of ultrathin Cr2Te3 films as candidates for developing room-temperature spintronics applications, and similar growth strategies could be applicable to fabricate other nanoscale layered magnetic compounds.