Pr_(0.5)Ca_(0.5)MnO_3/Si异质结输运特性和整流特性研究  

Transport and rectification properties of Pr_(0.5) Ca_(0.5) MnO_3 /Si heterojunction

作　　者：万冀豫[1] 金克新[1] 谭兴毅[1] 陈长乐[1] 

机构地区：[1]西北工业大学凝聚态结构与性质陕西省重点实验室,西安710072

出　　处：《物理学报》2010年第11期8137-8141,共5页Acta Physica Sinica

基　　金：国家自然科学基金(批准号:50702046);西北工业大学基础研究基金(批准号:NPU-FFR-JC200821);西北工业大学"翱翔之星"项目资助的课题~~

摘　　要：利用固相反应法制备Pr0.5Ca0.5MnO3(PCMO)靶材,并采用脉冲激光沉积法(PLD)在n型Si(111)基片上沉积PCMO外延薄膜,研究了薄膜的输运特性及薄膜与Si衬底形成异质结的整流特性.结果表明:在80—300K温度范围内,PCMO薄膜的阻温关系符合变程跳跃模型,随着温度的升高表现出从一维到二维再到三维的转变,分析认为可能源于轨道自由度对电子输运特性的影响.PCMO/Si异质结在磁场作用下整流特性得到改善,且在正向电流方向出现从正磁电阻到负磁电阻的过渡.Pr0.5 Ca0.5MnO3（PCMO） is been prepared by a solid-state reaction technique,and the thin film of PCMO is deposited on an n-type silicon substrate by a pulsed laser deposition method.Experimental results indicate the transport character of the film may be consistent with the variable range hopping model in a temperature range of 80—300 K,but it changes from one-dimension to two-dimensional and then turns three-dimensional with temperature increasing.It may be attributed to the effect of orbit order on the transport characteristics.The PCMO/Si heterojunction possesses good rectifieation property under a magnetic field,and at a positive voltage the heterojunction shows its magnetoresistance to have a remarkable transition from positive to negative.

关 键 词：Pr0.5Ca0.5MnO3 Si 整流 正磁电阻 

分 类 号：O484[理学—固体物理]