摘要
采用传统的高温固相反应法,制备钙钛矿锰氧化物(La0.9Gd0.1)4/3Sr5/3Mn2O7多晶样品,通过X射线衍射仪(XRD)、物性测量系统(PPMS)研究了样品的结构、磁性和电性。结果表明:样品为Sr3Ti2O7型四方结构,空间群为I4/mmm;同时,样品出现了含量非常少的杂质相。磁性测量表明:样品经历了铁磁到顺磁的转变,转变温度(T3DC)为75K。通过电性测量发现:T3DC也是金属性到绝缘性的转变温度。当T3DC<T<300K时,样品是以小极化子近邻跳跃的方式导电,说明电子在跃迁的过程中,其周围的极化子随电子一起运动。
（La0.9Gd0.1）4/3Sr5/3Mn2O7 polycrystalline sample was prepared by traclmonat sonu state tertt;t method and The structure, magnetic and electrical properties were investigated by measuring the M -T curve and R -T curve. Experimental results suggest the sample＇ structure was Sr3Ti207 type. It transforms from the three -di- mensional long - range ferromagnetic state to the paramagnetic order at T3D/C. In addition, Electrical properties meas- urement showed that insulator- metal transition temperature for（La0.9Gd0.1）4/3Sr5/3Mn2O7 just occurred at TcD. It can be seen from the fitted R -T curves that the electron conducting mechanism in the temperature range of T3D/C 〈 T 〈 300K is in accordance with small polarons hopping conduction, which indicates the surrounding of polaron fol- lows electronic in the process of movement.
出处
《阴山学刊（自然科学版）》
2014年第3期22-25,共4页
Yinshan Academic Journal(Natural Science Edition)
关键词
钙钛矿锰氧化物
磁性
电性
磁有序转变温度
perovskite -type manganites
magnetic property
electrical property and Magnetic orderly transi-tion temperature
