Phonon transport at interfaces between different phases of silicon and germanium
Phonon transport at interfaces between different phases of silicon and germanium
复制标题
DOI：
10.1063/1.4973573
复制
发表时间：
2017-01
影响因子：
3.2
通讯作者：
Kiarash Gordiz;A. Henry
中科院分区：
文献类型：
--
作者：
Kiarash Gordiz;A. Henry
目前对界面声子输运的认识和理解完全基于声子气体模型（PGM）。然而，对于无序材料，例如无定形材料，难以合理化PGM的使用。因此，基本上没有关于与非晶材料的界面的直觉。考虑到这种理解上的差距，在本文中，我们研究了热传导在不同的结晶和非晶Si/Ge界面使用最近开发的界面电导模态分析方法，它不依赖于PGM，因此可以处理界面与无序材料。结果表明，与非晶材料中较低平均自由程的论点相反，界面电导相当高。结果还表明，在12-13 THz频率范围内的界面振动模式是如此重要，以至于用速度重新缩放热浴（即，在非平衡态分子动力学模拟中）影响.
Current knowledge and understanding of phonon transport at interfaces are wholly based on the phonon gas model (PGM). However, it is difficult to rationalize the usage of the PGM for disordered materials, such as amorphous materials. Thus, there is essentially no intuition regarding interfaces with amorphous materials. Given this gap in understanding, herein we investigated heat conduction at different crystalline and amorphous Si/Ge interfaces using the recently developed interface conductance modal analysis method, which does not rely on the PGM and can therefore treat an interface with a disordered material. The results show that contrary to arguments based on lower mean free paths in amorphous materials, the interface conductances are quite high. The results also show that the interfacial modes of vibration in the frequency region of 12–13 THz are so important that perturbing the natural vibrations with velocity rescaling heat baths (i.e., in non-equilibrium molecular dynamics simulations) affects the...