Influence of the Co/Mn ratio on the magnetic order of Ca_3Co_(1+x)Mn_(1-x)O_6 compounds

摘要

A series of Ca3Co1+xMn1-xO6 (x =0, 0.05, and -0.05) compounds were synthesized that crystallized into rhombohedral structures with space group R-3c. Compared with the parent compound (x= 0), the freezing peak of the Co/Mn compensated samples (x = +/- 0.05) shifted to lower temperatures and became smeared. In addition, the coercive field H and remnant magnetization M r of the compensated samples measured at T =130 K also decreased. This study found that the short-range magnetic order of Ca3Co1+xMn1-xO6 compounds could be suppressed by tuning the Co/Mn ratio. Due to the suppression, the freezing magnetic moments in the compensated samples easily reversed magnetic field direction. Therefore, compared with the x = 0 sample, the time dependence of magnetization relaxation in the compensated samples exhibited a sharp decay rate, indicating fast dynamics.