Study of Dynamic Magnetism in Low Bandwidth Manganite Pr_1−x Ca_x MnO₃ (x=0.3−0.5) by Ac Susceptibility Measurements

The complex ac susceptibility is studied in the low bandwidth manganite Pr_1−xCa_xMnO₃ at doping range x = 0.3 − 0.5 with and without a superimposed background dc field. It is found that all the samples had a frustrated magnetic phase. The fraction of the frustrated magnetic phase in the samples diminished as the Ca concentration was increased. The suppression of the frustrated magnetic phase is explained by the formation of charge order (CO) phase around 250 K in the samples with x = 0.4 and 0.5. This result indicates that formation of CO-antiferromagnetic states reduces the magnetic frustration in the system and the spin glass behaviour is mainly associated with the coexisting antiferromagnetic—ferromagnetic phase in low bandwidth manganites.