Magnetic and transport properties of bilayered manganites La_(1.2)Sr_(1.8)Mn_(2-x)Ga_xO_7(x=0,0.08)  

作　　者：郑琳 周敏 赵建军 成昭华 张向群 邢茹 张雪峰 鲁毅 

机构地区：[1]Department of Physics,Baotou Normal University [2]State Key Laboratory of Magnetism and Beijing National Laboratory for Condensed Matter Physics,Institute of Physics,Chinese Academy of Sciences [3]Inner Mongolia Key Laboratory for Utilization of Bayan Obo Multi-Metallic Resources:Elected State Key Laboratory,Inner Mongolia University of Science and Technology

出　　处：《Chinese Physics B》2011年第8期408-410,共3页中国物理B（英文版）

基　　金：Project supported by the National Natural Science Foundation of China (Grant No. 50862007);the Inner Mongolia Natural Science Foundation of China (Grant No. 2009MS0101)

摘　　要：The magnetic and electrical properties of nonmagnetic Ga＋3 ion substitution for Mn site are investigated in the bilayer manganite La1.2Sr1.8Mn2-xGaxO7. When the Mn is substituted by Ga, the ferromagnetic property obviously weakens, the magnetic transition temperature decreases and a spin-glass behaviour occurs at low temperature. Meanwhile, doping causes the resistivity to dramatically increase, the metal-insulator transition temperature to disappear, and a greater magneto-resistance effect to occur at low temperature. These effects result from the fact that Ga substitution dilutes the magnetic active Mn-O-Mn network and weakens the double exchange interaction, and further suppresses ferromagnetic ordering and metallic conduction.The magnetic and electrical properties of nonmagnetic Ga＋3 ion substitution for Mn site are investigated in the bilayer manganite La1.2Sr1.8Mn2-xGaxO7. When the Mn is substituted by Ga, the ferromagnetic property obviously weakens, the magnetic transition temperature decreases and a spin-glass behaviour occurs at low temperature. Meanwhile, doping causes the resistivity to dramatically increase, the metal-insulator transition temperature to disappear, and a greater magneto-resistance effect to occur at low temperature. These effects result from the fact that Ga substitution dilutes the magnetic active Mn-O-Mn network and weakens the double exchange interaction, and further suppresses ferromagnetic ordering and metallic conduction.

关 键 词：magnetic property electrical property magnetoresistance effect metal-insulator transition 

分 类 号：O482.5[理学—固体物理]