SrTiO3的外延覆盖对La0．67Ca0．33MnO3／NdGaO3(001)薄膜中电荷有序相调控的影响  

CONTROLOF THE CHARGE-ORDERING-INSULATING PHASE IN EPITAXIAL La_(0.67)Ca_(0.33)MnO_3 THIN FILMS BY THE SrTiO_3 CAP LAYER

作　　者：孙正国[1] 梁艳[1] 宣晓峰[1] 吴文彬[1] 

机构地区：[1]中国科学技术大学物理系,合肥微尺度物质科学国家实验室(筹),合肥230026

出　　处：《低温物理学报》2013年第1期56-60,共5页Low Temperature Physical Letters

摘　　要：具有各向异性外延应变的La0.67Ca0.33MnO3/NdGaO3(001)外延薄膜,经过高温后退火处理可以诱导出电荷有序相,而外延应力场对电荷有序相的诱导机理有待进一步阐明.本文中,我们在La0.67Ca0.33MnO3薄膜上进一步外延SrTiO3覆盖层,以期从不同方面改变薄膜的应变状态.我们发现薄膜上方的应力钳制可改变来自衬底的各向异性应变,从而明显减弱薄膜中的电荷有序相.因此,除衬底外,外延覆盖层同样也可影响薄膜的应变状态、结构和物性.After post annealing, the charge-ordered insulating phase can be induced in La0.67Ca0.33MnO3 films un- der the anisotropic strain field supplied by NdGaO3 （001） substrates, hut at present the mechanism is far from being clear. In this paper, we grow the cap layer of SrTiO2 at various thicknesses on top of the Lao. 67 Ca0. 33 MnO3 films in order to change the strain effect. As a result, the charge ordering insulating phase was strongly weakened for the capped films, as reflected by the resistivity measurements. The results indicated that not only the substrate but also the capping layer could affect the strain state, structural and physical properties of the manganite films.

关 键 词：覆盖层 电荷有序相 后退火 

分 类 号：O484.1[理学—固体物理]