First-principles simulations of heat transport
First-principles simulations of heat transport
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DOI：
10.1103/physrevmaterials.1.060802
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发表时间：
2017-11
影响因子：
3.4
通讯作者：
Marcello Puligheddu;F. Gygi;G. Galli
中科院分区：
文献类型：
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作者：
Marcello Puligheddu;F. Gygi;G. Galli
近年来，从实验和理论两个方面报道了固体中热输运的研究进展。然而，研究固体热性质的高效和可预测的量子模拟框架还没有开发出来，其复杂性与经典模拟相同。本文提出了一种在接近平衡条件下通过从头算分子动力学来计算固体导热系数的方法，该方法只需要计算第一原理轨迹和原子力，从而避免了直接计算热流和能量密度。此外，该方法需要比普通分子动力学技术更短的顺序模拟时间，使其适用于密度泛函理论。我们讨论了具有代表性的氧化物氧化镁在不同温度下的结果以及有序和纳米结构的形貌，展示了该方法在不同条件下的性能。
Advances in understanding heat transport in solids were recently reported by both experiment and theory. However an efficient and predictive quantum simulation framework to investigate thermal properties of solids, with the same complexity as classical simulations, has not yet been developed. Here we present a method to compute the thermal conductivity of solids by performing ab initio molecular dynamics at close to equilibrium conditions, which only requires calculations of first-principles trajectories and atomic forces, thus avoiding direct computation of heat currents and energy densities. In addition the method requires much shorter sequential simulation times than ordinary molecular dynamics techniques, making it applicable within density functional theory. We discuss results for a representative oxide, MgO, at different temperatures and for ordered and nanostructured morphologies, showing the performance of the method in different conditions.