论文标题
重新访问纳米级的导热率和接口电导
Revisiting thermal conductivity and interface conductance at the nanoscale
论文作者
论文摘要
提出了一个半分析模型，用于研究纳米级的热传输，能够准确地描述均衡传输的效果和界面处的热传递的效果。我们的方法基于伪局部温度的定义，该温度根据其速度的方向区分了声子种群。这种形式主义会导致一组完整的方程式，即使在异质结构的情况下，也可以捕获纳米结构中的传热。该模型仅需要引入一个称为弹道热电导的新的固有热参数，而几何形状称为有效的导热率。最后，该模型能够在所有声子传输方式中对声子的蒙特卡洛模拟的准确高级数值结果：扩散（包括傅立叶热传输机制），弹道和中间的数字结果，即使涉及热界面。这种形式主义应在解释实验测量的解释时提供新的见解。
A semi-analytical model for studying thermal transport at the nanoscale, able to accurately describe both the effect of out of equilibrium transport and the thermal transfer at interfaces, is presented. Our approach is based on the definition of pseudo local temperatures distinguishing the phonon populations according to the direction of their velocity. This formalism leads to a complete set of equations capturing the heat transfer in nanostructures even in the case of hetero-structures. This model only requires introducing a new intrinsic thermal parameter called ballistic thermal conductance and a geometric one called the effective thermal conductivity. Finally, this model is able to reproduce accurately advanced numerical results of Monte Carlo simulation for phonons in all phonon transport regime: diffusive (as the Fourier heat transport regime is included), ballistic, and intermediate ones even if thermal interface are involved. This formalism should provide new insights in the interpretation of experimental measurements.
