Magnetic properties of Nd1-xKxMnO3 compounds

Polycrystalline Nd1-xKxMnO3 (x=0.10-0.20) compounds have been prepared in single phase form with Pbnm space group. The magnetic properties were studied by measuring dc magnetization and ac susceptibility. They exhibit paramagnetic to ferromagnetic transition with transition temperature ranging from 116 to 128 K. The magnetization data have been analyzed by using Brillouin function model and by taking into account the ferromagnetic interaction. The effective spin contribution towards ferromagnetic interaction and spin canting angle have been estimated. The spin canting angle is found to decrease with increase in doping. Magneto-caloric effect (MCE) has been studied and the maximum change in entropy was found to be 1.76 J/kg K for 1 T field. Metal-insulator transition and colossal magnetoresistance of the order of 60% for 1 T field have been observed for x=0.20 sample.