磁电异质结及器件应用

磁电异质结是由铁磁和铁电材料通过连接层耦合而成,其磁电效应来源于铁电相的压电效应和铁磁相的磁致伸缩效应.相对于颗粒混相磁电复合材料,层状磁电异质结材料具有更高的磁电耦合系数和更低的介电损耗,使得其在磁场传感器、能量收集器、天线以及存储器等领域都有着巨大的应用前景.本综述重点总结了磁电异质结材料的发展历程以及相关应用领域的最新进展,最后评述了磁电异质结材料发展的挑战和前景展望.     

由BaTiO3晶体结构相变时的介电特性研究其电场作用下的偶极子偏转路径

在不同频率和偏置电场下测量了BaTiO₃晶体从三方相到正交相再到四方相相变过程中的介电温谱.基于BaTiO₃晶体在电场作用下的偶极子偏转假设和介电特性实验结果,提出BaTiO₃各结构相在电场作用下的偶极子偏转路径可以由其相邻相的介电常数随温度的变化特性表现出来.推断出各结构相的偶极子偏转路径,以及偏置电场对偶极子偏转路径的影响. 关键词： 3晶体')" href="#">BaTiO₃晶体 介电特性 结构相变 偶极子偏转路径     

由BaTiO3晶体结构相变时的介电特性研究其电场作用下的偶极子偏转路径

在不同频率和偏置电场下测量了BaTiO3晶体从三方相到正交相再到四方相相变过程中的介电温谱.基于BaTiO3晶体在电场作用下的偶极子偏转假设和介电特性实验结果,提出BaTiO3各结构相在电场作用下的偶极子偏转路径可以由其相邻相的介电常数随温度的变化特性表现出来.推断出各结构相的偶极子偏转路径,以及偏置电场对偶极子偏转路径的影响.     

CuO added Pb_(0.92)Sr_(0.06)Ba_(0.02)(Mg_(1/3)Nb_(2/3))_(0.25)(Ti_(0.53)Zr_(0.47))_(0.75)O_3 ceramics sintered with Ag electrodes at 900℃ for multilayer piezoelectric actuator

CuO added Pb_(0.92)Sr_(0.06)Ba_(0.02)(Mg_(1/3)Nb_(2/3))_(0.25)(Ti_(0.53)Zr_(0.47))_(0.75)O_3 ceramics were studied to prepare high-quality multilayer piezoelectric actuators with pure Ag electrodes at 900℃. Cu O addition not only reduced the sintering temperature significantly from 1260℃ to 900℃ but also improved the ceramic density to 7.742 g/cm~3. The 0.7 wt.% Cu O added ceramic sintered at 900℃ shows the remnant polarization(P_r) of 40 μC/cm~2, 0.28% strain at 40 kV/cm, and the piezoelectric coefficient(d_(33)) of 630 pC/N. This ceramic shows a strong relaxor characteristic with a Curie temperature of 200℃. Furthermore, the 0.7 wt.% CuO added ceramic and pure Ag electrodes were co-fired at 900℃ to prepare a high-quality multilayer piezoelectric actuator with a d_(33) of over 450 pC/N per ceramic layer.     

Optical Dispersion Behavior and Band Gap Energy of Relaxor Ferroelectric 0.92Pb（Mgl/3Nb2/3）O3-0.08PbTiO3 Single Crystal

Refractive indices and extinction coefficients of O.92Pb（Mgl/3Nb2/3）O3-O.O8PbTiO~（PMN-O.OSPT） single crystaJ are investigated by variable angle spectroscopic ellipsometry （VASE） at different wavelengths. The parameters relative to the energy band structure are obtained by fitting to the single-oscillator dispersion equation, and the band gap energy is also deduced from the Tauc equation. Similar to most oxygen-octahedra ferroelectries, PMN-O.OSPT has the same dispersion behavior described by the refractive-index dispersion parameters.