理學院: 應用物理研究所指導教授: 陳政維潘明信Pan, Ming-HsinMing-HsinPan2017-03-062018-06-282017-03-062018-06-282016http://ntur.lib.ntu.edu.tw//handle/246246/276961The synthesis, characterization and dielectric properties of Praseodymium substituted calcium manganese oxides [PrxCa2-xMnO4] compounds were investigated. The dielectric properties of these compounds were studied in the frequency range from 20 Hz to 1 MHz between 10 K and 300 K. The low temperature dielectric properties were studied for the x = 0 ~ 0.5 compounds. Dielectric permittivity, dissipation factor, activation energy with thermally activated process, modulus spectra, and Cole-Cole plot have been investigated. The ε''(T) curves of samples show that the value of real dielectric permittivity has apparent high value (ε'' ~ 104) near 270 K for x = 0.2, 0.3, 0.4, 0.5. The tanδ(T) curves of these compounds exhibit dielectric relaxation at low temperature. The highest values in M”-T relation are found to increase with increasing with increasing x for the PrxCa2-xMnO4 system. The peak temperatures of tanδ shift from low to high temperatures as the test frequency  increases in all samples. In these samples we also observed Jonscher power law behavior.5254629 bytesapplication/pdf論文公開時間: 2017/1/1論文使用權限: 同意有償授權(權利金給回饋本人)介電性質鈣錳氧化物Dielectric responseManganese Oxidethesis10.6342/NTU201602135http://ntur.lib.ntu.edu.tw/bitstream/246246/276961/1/ntu-105-R03245004-1.pdf