Phonon scattering by nanoscale twin boundaries
Phonon scattering by nanoscale twin boundaries
复制标题
纳米级孪晶界的声子散射
DOI：
10.1016/j.nanoen.2016.12.026
复制
发表时间：
2017-02-01
期刊：
影响因子：
17.6
通讯作者：
Ren, Zhifeng
中科院分区：
文献类型：
--
作者：
Mao, Jun;Wang, Yumei;Ren, Zhifeng
孪晶作为晶体缺陷的一种，在各种材料体系中经常观察到。然而，它对声子散射的影响相比于其他缺陷的研究要少得多。理解双胞胎的声子散射效应的困难在于不可避免地存在其他缺陷（例如，晶界），这掩盖了孪晶的本征散射效应。为了解决这一问题，本工作制备了三种不同的InSb样品，包括微米级晶粒、纳米级晶粒和纳米级晶粒与纳米孪晶。通过比较不同样品之间的热导率，我们的结果明确地表明，声子确实可以被孪晶界散射。然而，与晶界形成鲜明对比的是，孪晶界的声子散射效应明显较弱，这可能归因于孪晶界的相干特性。
Twins, as one kind of crystal defects, are often been observed in various material systems. However, its effect on phonon scattering is much less investigated comparing to other defects. The difficulty in understanding the phonon scattering effect by twins lies in the inevitable presence of other defects (e.g., grain boundaries), which overshadow the intrinsic scattering effect by twins. In order to resolve the issue, three different kinds of InSb specimens with microscale grains, nanoscale grains, and nanoscale grains with nanotwins were prepared in this work. By comparing the thermal conductivities between different specimens, our results unambiguously show that phonons can indeed be scattered by twin boundaries. However, in a striking contrast to grain boundaries, phonon scattering effect by twin boundaries is noticeably weaker, which could be ascribed to the coherent characteristics of twin boundaries.