Temperature dependence of charge screening in Fe/SrTiO ₃ heterostructure

Abstract

The modulation of magnetization as a function of the temperature was studied in the Fe/SrTiO3 heterostructure by the electric field reversal. The magnetization is strong when the SrTiO3 layer is at the accumulation state but, when the SrTiO3 layer is at the depletion state, the magnetization of the Fe layer is weak. This phenomenon can be qualitatively explained by the variation in the electronic spin density of the Fe layer near the interface under reversing electric fields. The decrease in the change of the magnetoelectric coefficient as the temperature increases indicates that the charge screening effect is temperature dependent, which may be related to the change of the dielectric constant of the dielectric layer and the thermal motion of electrons in the Fe layer.