【锰基钙钛矿氧化物绝缘体-金属转变及超大磁电阻效应的起因】李衷怡.pdf
AdissertationSubmittedinFulfillmentof theRequirements for theDegree ofDoctor ofEngineering Origin ofInsulator-Metal Transition and Colossal Magnetoresistance in Manganese Perovskites Candidate:Li ZhongYi Major:MaterialPhysicsChemistry Supervisor:Prof.YuanSongLiu Prof.
华中科技大学博士学位论文 运行为也进行了模拟。结果表明,外加磁场使得I-M转变移向高温且转变附近电阻大 幅度下降,从而导致Tc附近出现CMR现象.为了增强模型的说服力,在第五章中选取了一系列的样品,如La2sAEisMnO3(AE =Ca、Ba、Sr和Cd),RE2sSr1sMnO3(RE=Nd和Pr)以及(La1-xY)2sCaisMnO(x =0,0,0以及0)作为研究对象,模拟了其在零场下的导电行为并与实验结果 作了比较,结果发现两者在定量上吻合得非常好。
华中科技大学博士学位论文 Chapter4is thekermelof thispaper.Basedon the analysis onexperiment data,it is According to this,a randomresistornetwork consisted ofPMIandFMMisgenerated through Monte Carlo method.The model qualitatively analyses the main character of manganese perovskite which is PMI at high temperatur