论文标题
对Anharmonic晶体中热空位的非阿里尼乌斯行为的理论见解
Theoretical Insights into Non-Arrhenius Behaviors of Thermal Vacancies in Anharmonic Crystals
论文作者
论文摘要
空缺是晶体中普遍的点缺陷，但它们的热反应难以捉摸。本文中，我们制定了一个简单的理论模型，以阐明加热过程中空置演变。通过量子统计力学中的力矩复发技术对振动激发进行彻底研究。在此基础上，我们对Sutton-Chen多体潜力进行了Ag，Cu和Ni的数值分析。我们的结果表明，众所周知的Arrhenius法律不足以描述空缺的扩散。具体而言，非谐作用导致空位形成的吉布斯能量的强烈非线性。以前的模拟和实验得到了很好的支持。
Vacancies are prevalent point defects in crystals, but their thermal responses are elusive. Herein, we formulate a simple theoretical model to shed light on the vacancy evolution during heating. Vibrational excitations are thoroughly investigated via moment recurrence techniques in quantum statistical mechanics. On that basis, we carry out numerical analyses for Ag, Cu, and Ni with the Sutton-Chen many-body potential. Our results reveal that the well-known Arrhenius law is insufficient to describe the proliferation of vacancies. Specifically, anharmonic effects lead to a strong nonlinearity in the Gibbs energy of vacancy formation. Our physical picture is well supported by previous simulations and experiments.
