Effect of Ca2MnO4 on the magnetic and electric properties in Ca3Mn2O7 ceramics prepared with different sintering temperature

Abstract

Hybrid improper ferroelectricity Ca3Mn2O7 is the promising multiferroic materials, which has attracted considerable attention due to their potential applications in areas such as electronic devices and storage media. The magnetic and electric properties of the layered perovskite Ca3Mn2O7 ceramics with different proportions of single-layer Ca2MnO4 phase synthesized by solid state reaction within adjusting the sintering temperature have been investigated. The x-ray diffraction patterns and the characteristic of magnetic transition from magnetization curves show that the ratio of Ca2MnO4 is reduced from 22.9 % of sintering at 1200 °C to 0 % of sintering at 1300 °C, which implies that the narrow suitable sintering temperature is the most factor for preparation of pure Ca3Mn2O7 ceramic samples. The ferroelectricity of all samples was investigated and the ferroelectricity decreased with the increase of Ca2MnO4 content due to the presence of non-ferroelectric Ca2MnO4 phase. The magnetoelectric coupling effect was discussed by the magnetization induced from the electric field. The results speculated that a small amount of Ca2MnO4 can improve the magnetoelectric coupling effect due to the interface effect in multiphase materials, which suggests that a new method to enhance the magnetoelectric coupling effect in Ca3Mn2O7 system.