Ab-initio study of magnetic properties and phase transitions in Ga (Mn) N with Monte Carlo approach

• The AKAI–KKR–CPA method has been applied to study the doped compound GaN:Mn.
• The local density approximation (LDA) has been applied.
• The ab-initio calculations have been performed.
• The density of states (DOS) have been plotted for differents doping concentrations, using Monte Carlo simulations.

On the basis of ab-initio calculations and Monte Carlo simulations the magnetic and electronic properties of Gallium nitride (GaN) doped with the transition metal Manganese (Mn) were studied. The ab initio calculations were done using the AKAI–KKR–CPA method within the Local Density Approximation (LDA) approximation. We doped our Diluted Magnetic Semiconductor (DMS), with different concentrations of magnetic impurities Mn and plotted the density of state (DOS) for each one. Showing a half-metallic behavior and ferromagnetic state especially for Ga0.95Mn0.05N making this DMS a strong candidate for spintronic applications. Moreover, the magnetization and susceptibility of our system as a function of the temperature has been calculated and give for various system size L to study the size effect. In addition, the transition temperature was deduced from the peak of the susceptibility. The Ab initio results are in good agreement with literature especially for (x=0.05) of Mn which gives the most interesting results.