Influence of Gd Doping on Magnetic Behavior in La0.67Sr0.33CoO3, La0.67Sr0.33MnO3

M-T curves, and M-H curves of La0.67-xGdxSr0.33CoO3, La0.67-xGdxSr0.33MnO3 (x=0.00, 0.05, 0.10, 0.20, 0.30, 0.40, 0.50, 0.60, 0.67) systems were measured. The results show that with increasing of doping Gd, magnetic structure of the La0.67-xGdxSr0.33CoO3 system exhibits cluster glass state, and the M-T curves of samples with x≥0.10 exhibit a peculiar phenomenon that M value rises sharply in a low temperature range; magnetic structure of La0.67-xGdxSr0.33MnO3 system changes from long-rang ferromagnetic order to cluster glass state, anti-ferromagnetic state, and the M-T curves of samples with x≥0.50 decline sharply in a low temperature range. The different phenomena shown by the two systems come from different coupling function between Gd and Co, Mn and from spin state transition of Co.