Monte Carlo simulation for calculating the exchange couplings in Ca2CrNO6 (N = Mo, Re) double perovskites

In the last few years there has been a growing interest in mixed magnetic oxides containing the transition-metal Cr, as they show interesting physical properties and a great ability to use in spintronic, photovoltaic and magnetocaloric applications. Therefore, several publications have appeared documenting Cr-based double perovskites, but very few have explored the promising compounds Ca2CrNO6 (N = Mo, Re). Exchange couplings in Ca2CrNO6 (N = Mo, Re) Double perovskites (DPs) have been fitted by Monte Carlo Simulation (MCS) calculations in the framework of Ising model by using a method based on a relation between internal energy per site and magnetization per site. The exchange couplings JCr−Mo=−1.977meV, JCr−Cr=4.614meV and JMo−Mo=1.481meV have been obtained for Ca2CrMoO6, while JCr−Re=−12.221meV, J'Cr−Cr=11.244meV and JRe-Re=11.492meV have been obtained for Ca2CrReO6. The role of exchange couplings strengths in the magnetism of this class of materials has been discussed. Internal energy per site has been calculated

Modelling of the ferroelectric and energy storage properties of PbZr1-xTixO3 thin films using Monte Carlo simulation

International audienceA Monte Carlo model was developed to study the ferroelectric and energy storage properties of PbZr1-xTixO3 (PZT). The proposed model aims to calculate the exchange coupling constants in ferroelectric PbZr1-xTixO3 thin films system, useful for Monte Carlo simulation within metropolis algorithm. Thus, the effect of temperature on the ferroelectric properties of the PZT thin films, such as, hysteresis loops, polarization and coercive field were investigated. Moreover, the phase diagram as a function of x values of T-i in PbZr1-xTixO3 was studied. The obtained P-E hysteresis loops permitted to predicte the energy storage properties of the studied system. A maximum of the recoverable energy density of 13.93 J cm(-3) was obtained with the energy density efficiency of 79% for x = 0. The obtained results are in good agreement with the reported experimental data for the same material