Microstructure-dependent magnetization of La0.67Ba0.33MnO3−δ manganites

The effects of microstructure on magnetization of La0.67Ba0.33MnO3−δ manganites are investigated. It is found that the manganites have different grain-growth configurations that strongly depend on sintering temperature. The La0.67Ba0.33MnO3−δ manganite sintered at 1573 K exhibits a lateral growth pattern while the one sintered at 1673 K grows with a concentric terrace pattern. These microstructures resulted in various magnetic properties of La0.67Ba0.33MnO3−δ manganite. The magnitude of magnetization at the magnetic field of 0.5 T for manganites sintered at 1673 K is found to be a factor of 2 higher than that for those sintered at 1573 K. The low-field magnetic susceptibility at low temperature is also found to be higher. This implies that the microstructure resulting from grain-growth may strongly influence magnetoresistance effects.