摘要
Strain engineering is a powerful tool to tailor the physical properties of materials coherently stacked in an epitaxial heterostructure. Such an approach, applied to the mature field of planar heteroepitaxy, has yielded a variety of new phenomena and devices. Recently, heteroepitaxial vertically aligned nanocomposites have emerged as alternatives to planar structures. Owing to the peculiar geometry of such nanoarchitectures, efficient strain control can be achieved, opening the way to novel functionalities. In this paper, we report a very large tensile axial strain in epitaxial transition metal nanowires embedded in an oxide matrix. We show that axial strains in excess of 1.5% can be sustained over a large thickness （a few hundred nanometers） in epitaxial nanowires having ultrasmall diameters （-3-6 nm）. The axial strain depends on the diameter of the nanowires, reflecting its epitaxial nature and the balance of interface and elastic energies. Furthermore, it is experimentally shown that such strain is metastable, in agreement with the calculations performed in the framework of the Frenkel-Kontorova model. The diameter dependence and metastability provide effective ways to control the strain, an appealing feature for the design of functional nanoarchitectures.
紧张工程是一个强大的工具定制协调地在取向附生的 heterostructure 叠的材料的物理性质。如此的一条途径，适用于平面 heteroepitaxy 的成熟领域，产出许多新现象和设备。最近， heteroepitaxial 垂直地排列了 nanocomposites 作为平面结构的选择出现了。由于如此的 nanoarchitectures 的古怪几何学，有效种类控制能被完成，打开到新奇功能的路。在这份报纸，我们在在一个氧化物矩阵嵌入的取向附生的转变金属 nanowires 报导一个很大的张力的轴的种类。我们证明超过 1.5% 罐头的轴的种类在有 ultrasmall 直径(36 nm ) 的取向附生的 nanowires 在大厚度(一些百纳米) 上被支撑。轴的种类取决于 nanowires 的直径，反映它的取向附生的性质和接口和有弹性的精力的平衡。而且，如此的种类是亚稳的，这试验性地被显示出，与在 Frenkel-Kontorova 模型的框架执行的计算一致。直径依赖和 metastability 提供有效方法控制种类，为功能的 nanoarchitectures 的设计的一个呼吁的特征。
