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arXiv 1306.2968cond-mat.str-el
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二维单带Hubbard-Holstein模型的行列式量子Monte Carlo研究

Determinant quantum Monte Carlo study of the two-dimensional single-band Hubbard-Holstein model

S. Johnston, E. A. Nowadnick, Y. F. Kung, B. Moritz, R. T. Scalettar, T. P. Devereaux

摘要:

我们用行列式量子蒙特卡罗方法对二维Hubbard-Holstein模型进行了数值研究。在这里,我们提出的方法的细节,强调治疗的晶格自由度,然后研究的填充和行为的费米子符号作为模型参数的函数。我们发现一个区域的参数空间与大荷斯坦耦合费米子符号恢复,尽管哈伯德相互作用的大值。这表明,在有限的载流子浓度的相关极化子的研究可能是访问DQMC模拟。然后,我们限制自己的半满模型,并检查反铁磁结构因子的演变,其他指标的反铁磁和电荷密度波顺序,和能量的电子和晶格自由度的函数的电子-声子耦合。从这一点上,我们找到了进一步的证据之间的竞争电荷密度波和反铁磁秩序在半填充。

英文摘要:

We have performed numerical studies of the Hubbard-Holstein model in two dimensions using determinant quantum Monte Carlo (DQMC). Here we present details of the method, emphasizing the treatment of the lattice degrees of freedom, and then study the filling and behavior of the fermion sign as a function of model parameters. We find a region of parameter space with large Holstein coupling where the fermion sign recovers despite large values of the Hubbard interaction. This indicates that studies of correlated polarons at finite carrier concentrations are likely accessible to DQMC simulations. We then restrict ourselves to the half-filled model and examine the evolution of the antiferromagnetic structure factor, other metrics for antiferromagnetic and charge-density-wave order, and energetics of the electronic and lattice degrees of freedom as a function of electron-phonon coupling. From this we find further evidence for a competition between charge-density-wave and antiferromagnetic order at half-filling.

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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