庞磁电阻Pr0．7Sr0．3MnO3／La0．5Ca0．5MnO3／Pr0.7Sr0.3MnO3三层膜的应变分析  

The analysis of strain states of giant magnetoresistive Pr_(0.7)Sr_(0.3)MnO_3/La_(0.5)Ca_(0.5)MnO_3/Pr_(0.7)Sr_(0.3)MnO_3 trilayers

作　　者：王海欧[1] 刘昊[1] 戴萍[1] 谭伟石[1] 吴小山[2] 贾全杰[3] 李晓龙[4] 

机构地区：[1]南京理工大学理学院应用物理系,南京210094 [2]南京大学固体微结构物理国家重点实验室南京大学物理系,南京210093 [3]中国科学院高能物理研究所,北京100039 [4]中国科学院上海应用物理研究所嘉定园区,上海201800

出　　处：《核技术》2012年第11期806-810,共5页Nuclear Techniques

基　　金：国家自然科学基金(批准号:11079022);江苏省自然科学基金(批准号:BK2006204)资助

摘　　要：用脉冲激光沉积法在MgO(001)衬底上生长了Pr0.7Sr0.3MnO3/La0.5Ca0.5MnO3/Pr0.7Sr0.3MnO3三层膜,其中Pr0.7Sr0.3MnO3的厚度为36nm,La0.5Ca0.5MnO3厚度分别为6、12、18、24、30和36 nm。通过高分辨X射线衍射的对称扫描和非对称扫描测量了三层膜中Pr0.7Sr0.3MnO3和La0.5Ca0.5MnO3的面外、面内晶格参数,研究了薄膜的晶格应变及其弛豫状况。结果表明,La0.5Ca0.5MnO3厚度的增加使薄膜面外应变完全弛豫,但面内的压应变仍然存在。三层膜应变弛豫状态由块材应变和Jahn-Teller应变共同决定。三层膜的应变弛豫机制与四方畸变的应变弛豫机制不同。块材应变和Jahn-Teller应变之间的相互竞争决定了薄膜的磁输运性质。Pr0,7Sr0.3MnO3/La0.5Ca0.5MnO3/Pr0.TSr0.3MnO3（PSMO/LCMO/PSMO） trilayers were deposited on （001）-oriented single crystal MgO by pulsed laser deposition. The thickness of both PSMO layers was 36 nm while the thickness of LCMO layer was 6, 12, 18, 24, 30 and 36nm, respectively. Out-of-plane and in-plane lattice parameters of trilayers were obtained by using symmetric scanning and asymmetric scanning mode of high resolution X-ray diffraction. Strain states of trilayers have been studied. The results showed that strain relaxation states of trilayers were decided by bulk strain and Jahn-Teller （JT） strain together. The mechanism for strain relaxation in trilayers is different from that for tetragonal distortion. The competition between bulk strain and Jahn-Teller （JT） strain played an important role in the magnetotransport and magnetic properties oftrilayers.

关 键 词：Pr0.7Sr0.3MnO3/La0.5Ca0.5MnO3/Pr0.7Sr0.3MnO3三层膜 高分辨X射线衍射 应变 

分 类 号：TG115.23[金属学及工艺—物理冶金]