金刚石纳米薄膜法向热导率的分子动力学模拟

结合卫星“微型核”的特点，用分子动力学模拟的方法研究了金刚石晶体的热导率与其厚度和温度的依变关系。采用平衡分子动力学的方法（EMD）模拟了晶向（001）的金刚石纳米薄膜法向热导率；采用非平衡分子动力学（NEMD）方法模拟了晶向（111）的金刚石法向热导率。模拟的结果表明：金刚石纳米薄膜的法向热导率显著小于对应大体积晶体的实验值，并随着厚度的增加而增加；在模拟范围内法向热导率与薄膜厚度呈近似线性关系；薄膜热导率在模拟厚度为2．05334nm时随着温度的增加而增加；在模拟厚度为2．874676nm时，则随着温度的增加而下降。

Molecular Dynamics Simulation on the Out-of Plane Thermal Conductivity of Diamond Crystal Thin Films

Combining the characteristic of minisize nucleus of satellite ,the Molecular Dynamics simulations are implemented to study the leaning relationship of the thermal conductivity and thickness of diamond crystal.The EMD is used to calculate the nanometer thin film thermal conductivity of diamond crystal at crystal direction(001),and the NEMD is used to calculate the nanometer thin film thermal conductivity of diamond crystal at crystal direction(111).The results of calculations demonstrated that the nanometer thin film thermal conductivity of diamond crystal is remarkably lower than the corresponding bulk experimental data and increase with increasing the film thickness,and the nanometer thin film thermal conductivity of diamond crystal relates to film thickness linearly in the simulative range.The nanometer thin film thermal conductivity increases with increasing the temperature at 2.05334nm,and the thermal conductivity decreases with increasing the temperature at 2.874676nm.