Elastically driven anisotropic percolation in electronic phase-separated manganites
Elastically driven anisotropic percolation in electronic phase-separated manganites
复制标题
DOI：
10.1038/nphys1419
复制
发表时间：
2009-12-01
期刊：
影响因子：
19.6
通讯作者：
Shen, J.
中科院分区：
文献类型：
--
作者：
Ward, T. Z.;Budai, J. D.;Shen, J.
复杂材料中电子相分离的存在与多种类型的外来行为有关，例如巨大的磁性，金属 - 绝缘体过渡和高温超导性（1-4）；然而，驱动共存电子相的形成的机制仍在争论（5-8）。在这里，我们报告了传输测量值，这些测量显示了由各向异性的氧化物膜和底物之间的各向异性长距离弹性耦合驱动的电子相域的优先取向。我们沿着伪内膜单晶薄膜锰矿的一个轴诱导各向异性电子域的形成，通过将其锁定在正骨底物上。沿两个垂直于平面轴的同时依赖温度依赖的电阻率测量表明，金属 - 绝缘体过渡温度和异常高的各向异性电阻率在巨大的差异上，这表明渗透性传导通道沿一个轴更容易打开。这些发现表明，相共存的起源比局部化学不均匀性更强烈地影响了菌株。
The presence of electronic phase separation in complex materials has been linked to many types of exotic behaviour, such as colossal magnetoresistance, the metal-insulator transition and high-temperature superconductivity(1-4); however, the mechanisms that drive the formation of coexisting electronic phases are still debated(5-8). Here we report transport measurements that show a preferential orientation of electronic phase domains driven by anisotropic long-range elastic coupling between a complex oxide film and substrate. We induce anisotropic electronic-domain formation along one axis of a pseudocubic perovskite single-crystal thin-film manganite by epitaxially locking it to an orthorhombic substrate. Simultaneous temperature-dependent resistivity measurements along the two perpendicular in-plane axes show substantial differences in the metal-insulator transition temperature and extraordinarily high anisotropic resistivities, which indicate that percolative conduction channels open more readily along one axis. These findings suggest that the origin of phase coexistence is much more strongly influenced by strain than by local chemical inhomogeneity.