DynaPhoPy: A code for extracting phonon quasiparticles from molecular dynamics simulations

We have developed a computational code, DynaPhoPy, that allow us to extract the microscopic anharmonic phonon properties from molecular dynamics (MD) simulations using the normal-mode-decomposition technique as presented by Sun et al. (2014). Using this code we calculated the quasiparticle phonon frequencies and linewidths of crystalline silicon at different temperatures using both of first-principles and the Tersoff empirical potential approaches. In this work we show the dependence of these properties on the temperature using both approaches and compare them with reported experimental data obtained by Raman spectroscopy (Balkanski et al., 1983; Tsu and Hernandez, 1982).本研究开发了一款名为DynaPhoPy的计算程序，可基于Sun等人（2014）提出的简正模分解技术，从分子动力学（MD）模拟中提取微观非谐声子（phonon）特性。借助该程序，本研究分别采用第一性原理与Tersoff经验势方法，计算了不同温度下晶体硅的准粒子声子频率与线宽。本研究展示了两种方法下上述特性随温度的变化规律，并将计算结果与已报道的拉曼光谱（Raman spectroscopy）实验数据（Balkanski等人，1983；Tsu与Hernandez，1982）进行了对比。