Enhanced multiferroicity in Mg-doped Ca3Co2-xMnxO6

Polycrystalline Ca3-xMgxCo2-yMnyO6 (y similar to 1.0) samples are prepared in order to investigate the A-site doping effect of Ca3Co2-yMnyO6 (y similar to 1.0). Compared with Ca3Co2-yMnyO6 (y similar to 1.0), the ferroelectric polarization and Curie point of Ca3-xMgxCo2-yMnyO6 (y similar to 1.0) at the maximal doping x similar to 0.3 are significantly enhanced. The magnetic order of Ca3-xMgxCo2-yMnyO6 (x similar to 0.3, y similar to 1.0) and thus ferroelectric order are more robust than the undoped compound. The slight lattice shrinking as a result of Mg substitution may contribute to the enhancement of exchange striction, leading to the changes in magnetic and ferroelectric properties.