Ni^(2+)掺杂钙钛矿锰氧化物La_(0.65)Ca_(0.35)MnO_(3)的磁性和临界行为研究  

Magnetic and Critical Behavior of Ni^(2+)-doped Perovskite Manganese Oxide La_(0.65)Ca_(0.35)MnO_(3)

作　　者：赵晶 赵建军[1] 邢茹[1] 李成 周敏[1] 云慧琴 金香[1] Zhao Jing;Zhao Jianjun;Xing Ru;Li Cheng;Zhou Min;Yun Huiqin;Jin Xiang(Key Laborato-ry of Magnetism and Magnetic Materials at Universities of Inner Mongolia,Baotou Teachers’Col-lege,Inner Mongolia University of Science and Technology,Baotou 014030,China)

机构地区：[1]内蒙古科技大学包头师范学院物理科学与技术学院,内蒙古自治区高等学校磁学与磁性材料重点实验室,内蒙古包头014030

出　　处：《中国稀土学报》2023年第5期894-903,I0002,共11页Journal of the Chinese Society of Rare Earths

基　　金：国家自然科学基金项目(11164019,51562032)资助。

摘　　要：通过传统的固相反应方法制备了多晶系列样品La_(0.65)Ca_(0.35)Mn_(1-x)Ni_(x)O_(3)(x=0, 0.1和0.3)。系统研究了Ni掺杂对预成型团簇相、磁熵变和临界行为的影响。结果表明,制备的多晶样品均具有立方钙钛矿结构,3个样品在低温磁转变温度以上均存在预成型团簇相。3个样品的临界行为与三临界模型拟合最好。掺杂样品x=0, x=0.1样品为一级相变到二级相变的过渡阶段,掺杂样品x=0.3在T_(C)附近的顺磁-铁磁转变为二级相变。样品外加磁场为7 T的最大磁熵变分别为7.70, 5.39和1.20 J·kg^(-1)·K^(-1)。A series of polycrystalline samples La_(0.65)Ca_(0.35)Mn_(1-x)Ni_(x)O_(3)(x=0,0.1,0.3)were prepared by traditional solid-state reaction method.The effects of Ni-doping on the preformed cluster phase,magnetic entropy change and critical behavior were systematically investigated.The results show that the prepared polycrystalline samples all have cubic perovskite structures,and all three samples have preformed cluster phases above the low-tempera⁃ture magnetic transition temperature.The critical behavior of three samples fits best with the tricritical model.The doped samples x=0 and x=0.1 are the transition stage from the first-order phase transition to the second-or⁃der phase transition,and the paramagnetic-ferromagnetic transition of the doped sample x=0.3 near T_(C) becomes the second-order phase transition.The maximum magnetic entropy changes of the samples with an applied mag⁃netic field of 7 T are 7.70,5.39 and 1.20 J·kg^(-1)·K^(-1),respectively.

关 键 词：预成型团簇相 磁相变 磁熵变 临界行为 稀土 

分 类 号：O469[理学—凝聚态物理]