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arXiv 2002.00928physics.plasm-ph
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跨越温度区的稠密等离子体电子输运模型

A Model of Electron Transport in Dense Plasmas Spanning Temperature Regimes

Nathaniel R. Shaffer, Charles E. Starrett

摘要:

将量子Landau-Fokker-Planck方程与平均力散射的概念相结合,提出了一个新的温热稠密等离子体中电子输运模型。我们获得的电导率和热导率在几个数量级的温度,从温暖的致密物质的条件下,热,非简并等离子体条件,包括具有挑战性的交叉制度之间的两者。Fokker-Planck碰撞理论的小角近似特性通过构造基于平均力散射的精确有效库仑模型得到了很好的缓解,与高保真量子模拟结果相比,该模型即使在低温下也能保持精确.电子-电子碰撞与电子-离子碰撞被同等对待。它们的准确处理被认为是必不可少的氢,并预计将是重要的其他低Z元素。我们发现,电子-电子散射仍然影响的热导率的值下降到温度略低于费米能量。由于泡利不相容原理和小角度近似之间的微妙相互作用,理论的准确性似乎只在非常低的温度下的热导率行为中动摇,因为它们属于电子-电子散射。即使在那里,该模型也与从头算模拟相当一致。

英文摘要:

We present a new model of electron transport in warm and hot dense plasmas which combines the quantum Landau-Fokker-Planck equation with the concept of mean-force scattering. We obtain electrical and thermal conductivities across several orders of magnitude in temperature, from warm dense matter conditions to hot, nondegenerate plasma conditions, including the challenging crossover regime between the two. The small-angle approximation characteristic of Fokker-Planck collision theories is mitigated to good effect by the construction of accurate effective Coulomb logarithms based on mean-force scattering, which allows the theory to remain accurate even at low temperatures, as compared with high-fidelity quantum simulation results. Electron-electron collisions are treated on equal footing as electron-ion collisions. Their accurate treatment is found to be essential for hydrogen, and is expected to be important to other low-Z elements. We find that electron-electron scattering remains influential to the value of the thermal conductivity down to temperatures somewhat below the Fermi energy. The accuracy of the theory seems to falter only for the behavior of the thermal conductivity at very low temperatures due to a subtle interplay between the Pauli exclusion principle and the small-angle approximation as they pertain to electron-electron scattering. Even there, the model is in fair agreement with ab initio simulations.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

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