Study of the Zn_0.75M_0.25Te (M = Fe, Co, Ni) diluted magnetic semiconductor system by first principles approach

Structure, mechanical and electronic properties of ternary Zn_0.75M_0.25Te (M = Fe, Co and Ni) diluted magnetic semiconductor system has been studied by first principles approach. Theoretical results revealed that the structure of all three alloys was stable in ferromagnetic phase. The enthalpies of formation were negative which also confirmed the structural stability of all three alloys in ferromagnetic phase. For Zn_0.75M_0.25Te (M = Fe, Co, Ni) alloys, the equilibrium lattice constants decreased from Fe to Ni. The band structure calculations showed that the Zn_0.75M_0.25Te (M = Fe, Co, Ni) alloys exhibit ferromagnetic semiconductor behavior. The energy band gap (E_g) increased from 2.19 eV to 2.33 eV with the addition of 25%M (M = Fe, Co, Ni) in Zn_0.75M_0.25Te alloys. For Zn_0.75M_0.25Te (M = Fe, Co, Ni) alloys, the magnetic moments of magnetic ions (Fe, Co, Ni) decreased from Fe to Ni, whereas small local magnetic moments were also found to appear at the non-magnetic (Zn and Te) atomic sites due to p-d hybridization. - Graphical abstract: Display Omitted - Highlights: • Ab initio calculations has been performed for Zn_0.75M_0.25Te (M = Fe, Co, Ni) alloys. • Equilibrium lattice constants were calculated for all three alloys. • All three alloys exhibit stable structure in ferromagnetic phase. • Band gap of Zn_0.75M_0.25Te (M = Fe, Co, Ni) alloys increased from Fe to Ni. • Mechanical and magnetic behavior was studied for all three alloys