Modeling of the magnetocaloric effect in Heusler Ni2MnGa alloy: Ab initio calculations and Monte Carlo simulations

The ab initio calculations, based on Density Functional Theory(DFT) approach and Full potential Linear Augmented Plane Wave (FLAPW) method, are used to investigate the electronic and magnetic properties of Heusler Ni2MnGa alloy. The magnetic moment considered to lie along (001) axes is computed. The obtained value of magnetic moment is used as input for Monte Carlo simulations to calculate the magnetic parameters. The Monte Carlo simulation is also used to study the magnetic properties of Ni2MnGa such as the Curie temperature TC(K). The phase transition becomes second-order at this point of TC(K). The heat specific and magnetic entropy are given. The magnetic entropy change and the adiabatic temperatures are deduced for a several magnetic field. Finally, we have determined the relative cooling power.