标题： 从第一性原理路径积分蒙特卡罗模拟中获得的温稠密电子气体的化学势 显示英文标题

标题： Chemical potential of the warm dense electron gas from ab initio path integral Monte Carlo simulations

摘要： 我们展示了针对温密均匀电子气体（UEG）化学势的大量新的\emph{从头计算}路径积分蒙特卡罗（PIMC）模拟结果，涵盖了广泛的密度和温度范围。 这是通过两种独立的方法实现的，i) 基于自由能的直接估算 [Dornheim\emph{等.}, arXiv:2407.01044] 和 ii) 在粒子数变化的 PIMC 模拟中使用直方图估计器。 我们通过实验确认了化学势的交换-关联（XC）部分与模拟电子数的预期反比例关系，这使得在不需要额外有限尺寸修正的情况下可以可靠地外推到热力学极限。 我们发现与 Groth\emph{等.}的 XC 自由能先前参数化结果（在$\Delta\mu_\textnormal{xc}\lesssim0.5\%$以内）非常一致 ~[\emph{物理评论快报}~\textbf{119}, 135001 (2017)]，这构成了当前最先进的 UEG 状态方程的重要交叉验证。 除了本身具有研究价值外，我们的研究为未来基于 PIMC 的真实温密物质系统的化学势研究奠定了基础，从氢气开始。 显示英文摘要

摘要： We present extensive new \emph{ab initio} path integral Monte Carlo (PIMC) simulation results for the chemical potential of the warm dense uniform electron gas (UEG), spanning a broad range of densities and temperatures. This is achieved by following two independent routes, i) based on the direct estimation of the free energy [Dornheim \emph{et al.}, arXiv:2407.01044] and ii) using a histogram estimator in PIMC simulations with a varying number of particles. We empirically confirm the expected inverse linear dependence of the exchange--correlation (XC) part of the chemical potential on the simulated number of electrons, which allows for a reliable extrapolation to the thermodynamic limit without the necessity for an additional finite-size correction. We find very good agreement (within $\Delta\mu_\textnormal{xc}\lesssim0.5\%$) with the previous parametrization of the XC-free energy by Groth \emph{et al.}~[\emph{Phys.~Rev.~Lett.}~\textbf{119}, 135001 (2017)], which constitutes an important cross validation of current state-of-the-art UEG equations of state. In addition to being interesting in its own right, our study constitutes the basis for the future PIMC based investigation of the chemical potential of real warm dense matter systems starting with hydrogen.