锰基钙钛矿型复合材料的电输运及低场磁电阻研究进展

Progress in research of the electric transport and low-field magnetoresistance in perovskite manganite composite material

锰基钙钛矿氧化物由于具有高的自旋极化率,其多晶样品表现出显著的低场磁电阻效应.通过把第二相材料引入到钙钛矿材料的表面或晶界,可以对颗粒边界进行表面改性,进而提高其电输运以及磁电阻性能.本文介绍了几类第二相材料,如绝缘体氧化物、金属材料、磁性材料和铁电材料,讨论了电输运性能和磁电阻提高的可能机制,展望了此类复合系统材料的良好前景.

Perovskite manganite oxides have a high spin polarization which induce the notable low-field manetoresistance effect in polycrystalline samples. Introduction second phase materials to surface or grain boundaries of perovskite materials can modify the property of granular boundaries and advance the electric transport and magnetic property furthermore. Sever- al types of second phase materials are introduced such as insulator oxides, metal materials, magnetic materials and ferroelec- tric materials, possible mechanisms of the electric transport and the magnetoresistance increase are discussed. Finaly the better prospect of such composite materials is viewed.