Modulation of magnetocrystalline anisotropy in FePt/PbTiO₃ heterostructures by ferroelectric polarization

Reducing the power consumption required for magnetization reversal is an urgent problem for spin storage device. Electric-field control of the magnetic anisotropy energy (MAE) using multiferroics materials is a promising method to solve this problem. Based on density functional theory, we investigated the effects of the ferroelectric polarization on MAE of FePt/PbTiO₃ multiferroic heterostructures. The MAEs of FePt monolayer with different polarization intensity are calculated. Our results indicated that the interfaces coupling between ferroelectric terminals and ferromagnetic terminals have a very large impact on the MAE of FePt monolayer. Moreover, with the reversal of the polarization orientation of ferroelectric PbTiO3 films, the MAE of ferromagnetic FePt monolayer has a monotonous but non-linear change. We demonstrated that the reversal of the polarization orientation results in a redistribution of charge density at the interface, thus resulting in a monotonic change in MAE with polarization intensity. It is provided an effective way to modulate the MAE by controlling the polarization intensity of ferroelectric layers.