Influence of the strong field in enhancing, electronic magnetic and optical properties of Mn-doped MgO

The local spin density approximation with Hubbard-like coulomb term based on first principles calculations are used to investigate a substitute doping of transition metal Mn in MgO. Under the crystal field theory and according to the intensity of the ligand field, the d4-d8 transition elements can have two possible configurations such as the case of Mn(d5), in its low spin configuration that represents a strong field, the Mn+2 doped MgO material has a half-metallic character in the two proposed studies approximations: the local spin density approximation (LSDA) and (LSDA + U), a character that will enable to change the magnetic, electronic and optical properties., This result is supported by the sp-d exchange mechanism calculation confirming that the coupling between impurity and ligand is completely ferromagnetic. The material has a magnetic moment of about 1 μB, mainly due to the Mn impurity of around 95% in LSDA + U case. In optical propriety the material shows a slight spin polarization and reduction of band gap of around 5% with strong filed in LSDA + U case.