The Effect of BN Doping and Interstitialing Atom on the Structure and Physical Properties of C and La0.7Ca0.3MnO3
|School||Huazhong University of Science and Technology|
|Course||Materials Physics and Chemistry|
|Keywords||Perovskite manganese oxides Complex CBN ternary compound Metal - insulator transition Large magnetoresistance (CMR) effect|
Perovskite structure manganese oxide for people to study the physics of strongly correlated electron system provides an ideal natural laboratory , which allows the presence of a variety of fundamental interactions , and these interactions can be artificially needed to be changed ; same time because the application prospects such oxides exhibit very large magnetoresistance (CMR) effect , makes its study has become one of condensed matter physics and materials science frontier subject . This thesis preferential hole doped perovskite structure of rare earth manganese oxides as the population , it is with some oxide composite, these composite samples under the transport behavior in the zero-field and processing field . The latest research progress of the first chapter brief summary of the perovskite structure manganese oxide , as well as the purpose of the paper . Second chapter brief summary of the CBN ternary compounds latest research progress . Chapter III detailed description of the sample preparation process , including the solid state reaction method , mechanical milling method and composite material technology , and done a detailed analysis of the impact of the samples prepared by different preparation process , and trying to find what we need best sample preparation process . The fourth chapter of the CBN phase structure and the electronic structure of the ternary compound . Chapter BN after incorporation in LCMO base body , the resistance-temperature characteristics and changes in the structure . We found that all the samples having a perovskite structure , BN only stay LCMO grain boundary . For the high - doped portion ( GT ; 20 % ) , samples of the metal - insulator transition temperature with the BN doping for the low doped portion (lt; 20%), samples of the metal - insulator little change transition temperature ( 263K ) ; the amount of increase becomes smaller.