Department of Mechanical Engineering, Northwestern University, Evanston, Illinois 60208-3111, USA.
Nano Lett. 2011 Feb 9;11(2):548-55. doi: 10.1021/nl103450e. Epub 2010 Dec 20.
We characterized the elastic properties of GaN nanowires grown along different crystallographic orientations. In situ transmission electron microscopy tensile tests were conducted using a MEMS-based nanoscale testing system. Complementary atomistic simulations were performed using density functional theory and molecular dynamics. Our work establishes that elasticity size dependence is limited to nanowires with diameters smaller than 20 nm. For larger diameters, the elastic modulus converges to the bulk values of 300 GPa for c-axis and 267 GPa for a- and m-axis.
我们对沿不同晶向生长的 GaN 纳米线的弹性性质进行了研究。采用基于 MEMS 的纳米级测试系统进行了原位透射电子显微镜拉伸测试。使用密度泛函理论和分子动力学进行了补充的原子模拟。我们的工作表明，弹性尺寸依赖性仅限于直径小于 20nm 的纳米线。对于更大的直径，弹性模量收敛于 c 轴的 300GPa 和 a 轴和 m 轴的 267GPa 的体值。
