Magnetic and Electronic Properties of Transition Metal-Doped AlN Nanosheets: a First-Principles Study for Spintronic Applications

We present here a Density Functional Theory-based ab initio study of the structural, electronic, magnetic and optical properties of a transition metal-doped AlN nanosheet. From the total energy difference, the stable ferromagnetic or antiferromagnetic configuration is determined. We find that the pure AlN nanosheet is a nonmagnetic, wide-bandgap (3.28 eV) semiconductor, while transition metal atoms induce magnetic moments, leading to structural changes around the dopant and neighboring atoms. The calculated partial DOS shows that d orbitals of transition metal atoms are strongly hybridized with the p orbitals of N near the Fermi level, resulting in a transition from semiconducting to half-metallic behavior. Cr- and Cu-doped AlN nanosheets, which exhibit 100% spin polarization, are promising candidates for spintronic devices due to their strong half-metallic ferromagnetic properties. These findings suggest that TM-doped AlN nanosheets are promising for applications in nanodevices and spintronic devices based on low-dimensional nanostructures.