Thermal conductance calculations of silicon nanowires: comparison with diamond nanowires.
Thermal conductance calculations of silicon nanowires: comparison with diamond nanowires.
复制标题
DOI：
10.1186/1556-276x-8-256
复制
发表时间：
2013-05-29
影响因子：
--
通讯作者：
Hirose K
中科院分区：
文献类型：
--
作者：
Yamamoto K;Ishii H;Kobayashi N;Hirose K
利用原子间Tersoff-Brenner势，用非平衡格林函数方法计算了直径为1~5 nm的硅纳米线(SiNWs)在有空位缺陷和无空位缺陷时的声子热导。为了进行比较，我们还给出了金刚石纳米线的声子热导计算。对于SiNW中的两种空位缺陷，即“中心缺陷”和“表面缺陷”，我们发现中心缺陷比表面缺陷对热导的影响要大得多。我们还发现，在100和300K以上，热导的性质从通常的与直径的平方(截面积)成正比，变成了在低温下完全不依赖于直径的反常行为。这种交叉归因于热导的量子化。
We present phonon thermal conductance calculations for silicon nanowires (SiNWs) with diameters ranging from 1 to 5 nm with and without vacancy defects by the non-equilibrium Green’s function technique using the interatomic Tersoff-Brenner potentials. For the comparison, we also present phonon thermal conductance calculations for diamond nanowires. For two types of vacancy defects in the SiNW, a ‘center defect’ and a ‘surface defect’, we found that a center-defect reduces thermal conductance much more than a surface defect. We also found that the thermal conductance changes its character from the usual behavior, in proportion to the square of diameter (the cross-sectional area) for over 100 and 300 K, to the unusual one, not dependent on its diameter at all at low temperature. The crossover is attributed to the quantization of thermal conductance.