论文标题
Fermionic Path积分蒙特卡洛法的有限温度电子气体的热力学特性
Thermodynamic properties of the finite-temperature electron gas by the fermionic path integral Monte Carlo method
论文作者
论文摘要
已开发并应用了新的{\ em ab intib}量子路径积分蒙特卡洛方法，并应用于强耦合退化的均匀电子气体（UEG）的熵差计算，这是一种已知的简单金属模型。在宽密度和温度范围内，在有限温度下进行了计算。获得的数据对于密度功能理论可能至关重要。开发方法的改进包括基本蒙特卡洛细胞中费米的库仑和交换相互作用，以及其周期性图像以及路径积分中变量的正确变化。即使在温度下，开发的方法也与费米能量低四倍，与费米能量的可用结果相吻合，并且实际上不会遭受“费米金符号问题”的困扰，该问题发生在标准路径积分蒙特卡洛模拟的变性费米子系统中。提出的结果包括配对分布函数，压力的等温线，内部能量和熵变化，并在较大的密度和温度下强烈耦合和退化UEG。
The new {\em ab initio} quantum path integral Monte Carlo approach has been developed and applied for the entropy difference calculations for the strongly coupled degenerated uniform electron gas (UEG), a well--known model of simple metals. Calculations have been carried out at finite temperature in canonical ensemble over the wide density and temperature ranges. Obtained data may be crucial for density functional theory. Improvements of the developed approach include the Coulomb and exchange interaction of fermions in the basic Monte Carlo cell and its periodic images and the proper change of variables in the path integral measure. The developed approach shows good agreement with available results for fermions even at temperature four times less than the Fermi energy and practically doesn't suffer from the "fermionic sign problem", which takes place in standard path integral Monte Carlo simulations of degenerate fermionic systems. Presented results include pair distribution functions, isochors and isotherms of pressure, internal energy and entropy change in strongly coupled and degenerate UEG in a wide range of density and temperature.
