基于平衡态和非平衡态分子动力学模拟研究锗烯热导率

Based on the equilibrium and the non-equilibrium molecular dynamics study of thermal conductivity ofSgermanene

摘要:

利用平衡态和非平衡态分子动力学模拟的方法计算了锗烯的热导率。首先，应用平衡态方法模拟了锗烯的热导率并进一步计算了热导率分解的各个分量。与石墨烯不同，锗烯热导率较小且 分量占主导。其次，应用非平衡态方法模拟计算了一系列长度的锗烯热导率，通过拟合得到不依赖长度的收敛热导率。最后，比较平衡态和非平衡态两种模拟方法得到的结果。发现不仅在数值上结果是一致的，而且通过拟合声子群速度将平衡态数据转换为长度依赖关系，也可以与非平衡态数据很好的重合。因此，基于平衡态和非平衡态两种方法应用GPUMD程序模拟计算的锗烯热导率都是有效且等价的。

Abstract:

The thermal conductivity of germanene is calculated using the equilibrium and the non-equilibrium molecular dynamics simulations. Firstly, the thermal conductivity of germanene is simulated by the equilibrium method, and the components of thermal conductivity decomposition are further calculated. Unlike graphene, the thermal conductivity of germanene is small and the component is dominant. Secondly, the non-equilibrium method is used to simulate and calculate the thermal conductivity of a series of lengths of germanene. It is obtained that the thermal conductivity of the convergence with the non-dependent length by fitting. Finally, it is found that not only on the numerical results are consistent by comparing both the equilibrium and the non-equilibrium methods, and the simulation data of the equilibrium can be transformed into a length dependent relation by fitting the phonon group velocity, which can also be overlapped with the non-equilibrium data points. Therefore, we have determined that the thermal conductivity of germanene are effective and equivalent, which are calculated using the GPUMD package based on both the equilibrium and the non-equilibrium methods.