Shaffer Nathaniel R, Starrett Charles E
Los Alamos National Laboratory, P. O. Box 1663, Los Alamos, New Mexico 87545, USA.
Phys Rev E. 2020 Jan;101(1-1):013208. doi: 10.1103/PhysRevE.101.013208.
Most treatments of electron-electron correlations in dense plasmas either ignore them entirely (random phase approximation) or neglect the role of ions (jellium approximation). In this work, we go beyond both these approximations to derive a formula for the electron-electron static structure factor which properly accounts for the contributions of both ionic structure and quantum-mechanical dynamic response in the electrons. The result can be viewed as a natural extension of the quantum Ornstein-Zernike theory of ionic and electronic correlations, and it is suitable for dense plasmas in which the ions are classical and the conduction electrons are quantum-mechanical. The corresponding electron-electron pair distribution functions are compared with the results of path integral Monte Carlo simulations, showing good agreement whenever no strong electron resonance states are present. We construct approximate potentials of mean force which describe the effective screened interaction between electrons. Significant deviations from Debye-Hückel screening are present at temperatures and densities relevant to high-energy density experiments involving warm and hot dense plasmas. The presence of correlations between conduction electrons is likely to influence the electron-electron contribution to the electrical and thermal conductivity. It is expected that excitation processes involving the conduction electrons (e.g., free-free absorption) will also be affected.
在稠密等离子体中，大多数处理电子 - 电子相关性的方法要么完全忽略它们（随机相位近似），要么忽略离子的作用（凝胶模型近似）。在这项工作中，我们超越了这两种近似，推导出一个电子 - 电子静态结构因子的公式，该公式恰当地考虑了离子结构和电子中量子力学动态响应的贡献。该结果可被视为离子和电子相关性的量子奥恩斯坦 - 泽尔尼克理论的自然扩展，适用于离子为经典粒子且传导电子为量子力学粒子的稠密等离子体。将相应的电子 - 电子对分布函数与路径积分蒙特卡罗模拟结果进行比较，结果表明，只要不存在强电子共振态，二者就具有良好的一致性。我们构建了描述电子间有效屏蔽相互作用的平均力近似势。在与涉及温热和热稠密等离子体的高能量密度实验相关的温度和密度下，存在与德拜 - 休克尔屏蔽的显著偏差。传导电子之间相关性的存在可能会影响电子对电导率和热导率的贡献。预计涉及传导电子的激发过程（例如自由 - 自由吸收）也将受到影响。
