论文标题
有限温度下均匀电子气体的无用辅助场量蒙特卡洛透视：问题，观察和基准研究
A Phaseless Auxiliary-Field Quantum Monte Carlo Perspective on the Uniform Electron Gas at Finite Temperatures: Issues, Observations, and Benchmark Study
论文作者
论文摘要
我们使用统一电子气体作为模型研究了无量辅助辅助场量子量蒙特卡洛（pH-ft-ft-afqmc）方法的生存能力。通过与精确结果和有限温度耦合簇理论的比较，我们发现pH-ft-ft-afqMC在高到中间电子密度时足够准确。我们在分析上和数值上都表明，有限温度下的无量限制与零温度对应物（即pH-ZT-AFQMC）根本不同，通常不应该期望pH-FT-ft-afqMC在低温限制中与PH-ZT-AFQMC一致。通过有效的实施，我们能够将交换与相关能量与热力学限制中的现有结果进行比较，并发现现有的参数化非常准确。特别是，我们发现，与已知参数化相比，pH-ft-ft-ft-afqmc交换和相关能量与$θ\ le0.5 $和$ r_s \ le 2 $的限制路径综合蒙特卡洛相比，与已知的参数化更加一致。
We investigate the viability of the phaseless finite temperature auxiliary field quantum Monte Carlo (ph-FT-AFQMC) method for ab initio systems using the uniform electron gas as a model. Through comparisons with exact results and finite temperature coupled cluster theory, we find that ph-FT-AFQMC is sufficiently accurate at high to intermediate electronic densities. We show both analytically and numerically that the phaseless constraint at finite temperature is fundamentally different from its zero temperature counterpart (i.e., ph-ZT-AFQMC) and generally one should not expect ph-FT-AFQMC to agree with ph-ZT-AFQMC in the low temperature limit. With an efficient implementation, we are able to compare exchange-correlation energies to existing results in the thermodynamic limit and find that existing parameterizations are highly accurate. In particular, we found that ph-FT-AFQMC exchange-correlation energies are in a better agreement with a known parametrization than is restricted path-integral Monte Carlo in the regime of $Θ\le0.5$ and $r_s \le 2$, which highlights the strength of ph-FT-AFQMC.
