First principles study of structural, elastic, electronic and magnetic properties of Mn-doped AlY (Y=N, P, As) compounds

We investigate zinc-blende phase Al_0.75Mn_0.25Y (Y=N, P, As) compounds using full-potential linear-augmented-plane wave plus local-orbital method. For computing structural and elastic properties the Generalized Gradient Approximation (GGA) has been used; whereas the electronic and magnetic properties are examined at the optimized GGA lattice parameters by employing modified Becke and Johnson local density approximation. All these compounds are found to be stable in ferromagnetic ordering in the zinc-blende structure which is supported by the computed elastic constants. The nature of electronic band structure are calculated and the nature of band gaps in the doped system is analyzed. The results are examined to identify exchange mechanism which is the main source of introducing ferromagnetism in the compounds under investigation. Spin charge density contour plots in the (1 1 0) plane and the evaluation of s–p and p–d exchange constants (N₀α and N₀β) are evaluated for understanding bonding and exchange splitting process, respectively. - Highlights: • Spin-polarized DFT investigation Mn-doped AlN, AlP and AlAs is reported. • Structrual and elastic properites are computed for evaluating stability. • mBJLDA used for appropriate treatment of d states of Mn for electronic properties. • Half metallicity, ferromagnetic stability and exchange constants are evaluated