Enhanced multiferroicity in Mg-doped Ca(3)Co(2-x)Mn(x)O(6)

Polycrystalline Ca(3-x)Mg(x)Co(2-y)Mn(y)O(6) (y similar to 1.0) samples are prepared in order to investigate the A-site doping effect of Ca(3)Co(2-y)Mn(y)O(6) (y similar to 1.0). Compared with Ca(3)Co(2-y)Mn(y)O(6) (y similar to 1.0), the ferroelectric polarization and Curie point of Ca(3-x)Mg(x)Co(2-y)Mn(y)O(6) (y similar to 1.0) at the maximal doping x similar to 0.3 are significantly enhanced. The magnetic order of Ca(3-x)Mg(x)Co(2-y)Mn(y)O(6) (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.