Studies of Microstructure and Electro-Magnetic Transport Property of La_0.67Ca_0.33MnO₃ Ceramic

Abstract:

The positron annihilation techniques and X-ray diffraction have been used to study the microstructure of the La_0.67Ca_0.33MnO₃ ceramics prepared by the solid-state reaction method at different sintered temperatures (T=1573K, 1623K, 1673K, 1723K, 1773K, 1823K). And the electro-magnetic transport behavior of the samples was measured by VSM and Resistivity modular on PPMS. According to these results, all samples show a perovskite structure, the ferromagnetic-paramagnetic and metal-insulator transitions occur at the transition temperature T_c and T_MI, respectively, which is almost the same. For La_0.67Ca_0.33MnO₃ sintered at 1673K, the mean positron lifetime is the largest, the maximum value of the magnetization is achieved on the magnetization-temperature curve at H=0.2mT, while the transition temperature occurs at about 244K.

• Periodical: Defect and Diffusion Forum (Volume 373)
• Pages: 205-208
• DOI: https://doi.org/10.4028/www.scientific.net/DDF.373.205
• Online since: March 2017
• Authors: Shou Lei Xu*, Er Juan Xie, Xiu Qing Cao, Yu Yang Huang, Ding Kang Xiong, Wen Deng
• Keywords: Electro-Magnetic Transport Property, La_0.67Ca_0.33MnO₃ Ceramic, Microstructure, Sintered Temperature

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