论文标题
部分可观测时空混沌系统的无模型预测
Parameter-free prediction of phase transition in PbTiO3 through combination of quantum mechanics and statistical mechanics
论文作者
论文摘要
铁电材料的热力学及其对副型（FE-PE）转变的热力学通常由现象学Landau理论来描述，最近由有效的哈密顿量和各种潜力来描述，所有这些都具有适用于实验性或理论数据的模型参数。在这里，我们表明Zentropy理论认为系统的总熵是系统可能会体验的配置的加权总和，并且配置之间的统计熵可以预测Fe-PE转换而无需拟合参数。对于PBTIO3，除了没有域壁的Fe配置的基底状态外，配置被识别为具有90-或180度域壁的Fe配置。通过基于文献中的密度功能理论的第一原理计算预测的域壁能量是唯一的输入，预测PBTIO3的Fe-PE跃迁表现出与实验的显着一致性，揭示了过渡的显微镜基础。
Thermodynamics of ferroelectric materials and their ferroelectric to paraelectric (FE-PE) transitions including those in PbTiO3 is commonly described by the phenomenological Landau theory and more recently by effective Hamiltonian and various potentials, all with model parameters fitted to experimental or theoretical data. Here we show that the zentropy theory, which considers the total entropy of a system as a weighted sum of entropies of configurations that the system may experience and the statistical entropy among the configurations, can predict the FE-PE transition without fitting parameters. For PbTiO3, the configurations are identified as the FE configurations with 90- or 180-degree domain walls in addition to the ground state of the FE configuration without domain wall. With the domain wall energies predicted from first-principles calculations based on the density functional theory in the literature as the only inputs, the FE-PE transition for PbTiO3 is predicted showing remarkable agreement with experiments, unveiling the microscopic fundamentals of the transition.
