Résumé:
The objective of our work is to calculate the structural, electronic and
magnetic properties of dilute magnetic semiconductors Zn0.75MT0.25O (MT = Co, Fe,
Mn), in the zinc blende phase. We have performed a theoretical study using allelectron full-potential linearized Muffin-Tin orbitals (FP-LMTO) calculations within
the framework of the density functional theory (DFT) and the generalized gradient
approximation (GGA), implemented in the ‹‹ LM suite 7 ›› code.
The calculated structural properties such as the equilibrium lattice parameter
a0, the bulk modulus ????’0 and its pressure derivative ????’0 are in good agreement with the
available data.
The analysis of band structures and density of states (DOS) show that the
Zn0.75MT0.25O (MT = Co, Fe, Mn) compounds present a direct band gap at the point
of high symmetry (Γ), and are ferromagnetic semiconductors.
The p-d hybridization between the Co/Fe/Mn-d and O-p states reduces the
magnetic moment of Co, Fe and Mn from their free space charge values, and produces
magnetic moments on non-magnetic sites of Zn and O.
