论文标题
扰动理论和质量序列合金中的热传输：绿色功能方法的见解
Perturbation theory and thermal transport in mass-disordered alloys: Insights from Green's function methods
论文作者
论文摘要
鉴于其弱和稀释障碍的基本假设，使用了最低级量子扰动理论（Fermi的黄金法则），用于在几种半导体合金中预测几种半导体合金中的导热性。在本文中，我们通过重点关注最大质量划分的Mg $ _2 $ si $ _ {1-x} $ sn $ _x $的情况来解释这是怎么可能的。我们使用Chebyshev多项式的Green的功能方法，该方法允许在非常大的系统（数千万原子）上对疾病进行全面处理，以探测单个声子宽度和频率分辨的热传输。我们证明，扰动理论的成功源于声子绿色功能中的质量障碍项的特定形式以及非谐和无序散射之间的相互作用。
Lowest-order quantum perturbation theory (Fermi's golden rule) for phonon-disorder scattering has been used to predict thermal conductivities in several semiconducting alloys with surprising success given its underlying hypothesis of weak and dilute disorder. In this paper, we explain how this is possible by focusing on the case of maximally mass-disordered Mg$_2$Si$_{1-x}$Sn$_x$. We use a Chebyshev polynomials Green's function method that allows a full treatment of disorder on very large systems (tens of millions of atoms) to probe individual phonon linewidths and frequency-resolved thermal transport. We demonstrate that the success of perturbation theory originates from the specific form of mass disorder terms in the phonon Green's function and from the interplay between anharmonic and disorder scattering.
