重构蓝宝石表面诱导La_0.7Sr_0.3MnO₃纳米结构及其性质研究  

Study on the Properties of La0.7Sr0.3MnO3 Nanostructures Induced by Reconstruction of Sapphire surface

作　　者：王明洁 吉彦达 杨浩 

机构地区：[1]南京航空航天大学理学院,江苏 南京

出　　处：《应用物理》2020年第2期131-138,共8页Applied Physics

摘　　要：二维La0.7Sr0.3MnO3纳米薄膜在由m面蓝宝石表面重构的具有纳米凹槽的横向纳米复合材料下制备。通过XRD测试样品晶体结构,确定样品物质组成,用原子力显微镜(AFM)测试薄膜表面形貌。我们通过范德堡法测试了薄膜温度–电阻(R-T)曲线来表征其金属-绝缘体转变(MIT)特性,发现在重构蓝宝石基片的不同取向,即在沟道的不同方向上,其MIT表现出各向异性。从磁化强度随温度的变化,我们发现LSMO薄膜显示出顺磁–铁磁(PM-FM)相变,并且在沟道的不同方向上,其PM-FM也表现出各向异性。Two-dimensional La0.7Sr0.3MnO3 nanofilms were prepared on transverse nanocomposites with nanogrooves reconstructed from the surface of sapphire with m surface. The crystal structure and the composition of the samples were determined by X-Ray Diffraction (XRD), and the surface morphology of the films was tested by atomic force microscope (AFM). The Vanderbilt method was applied to measure the temperature-resistance (R-T) curve of the films in order to characterize its MIT properties. It is found that the MIT of reconstructed sapphire substrate shows anisotropy in different orientations of channels. From the variation of magnetization intensity with temperature, we found that LSMO film showed paramagnetic-ferromagnetic (PM-FM) phase transition, and its PM-FM also showed anisotropy in different directions of the channel.

关 键 词：表面重构 蓝宝石 LSMO MIT各向异性 PM-FM各向异性 

分 类 号：TB3[一般工业技术—材料科学与工程]