论文标题
债券拉伸电子互动的混合蒙特卡洛研究Babio $ _3 $
A hybrid Monte Carlo study of bond-stretching electron-phonon interactions and charge order in BaBiO$_3$
论文作者
论文摘要
电子phonon（$ e $ -ph）相互作用与电荷密度波（CDW）订单之间的关系尚未解决。我们使用父级复合babio $ _3 $的非扰动混合蒙特卡洛计算来解决这个问题。我们的模型包括BI $ 6S $和o $2p_σ$轨道以及通过BI-O Hopping Integrales的调制光子词与光学声子的Bi-O键拉伸分支结合。我们模拟了最多4000个轨道的三维簇，并使用{\ it Ab intibion}电子结构计算和声子Energy $ \HBARΩ_0= 60 $ 〜MEV采取输入模型参数。我们的结果表明，尽管相对较小的无尺寸耦合，但与键拉伸模式的耦合足以重现该系统中的CDW过渡。我们还发现过渡与弱耦合Peierls的图片偏离。这项工作表明，轨道空间中的偏离$ e $ e $ ph相互作用对于建立二态相图至关重要。
The relationship between electron-phonon ($e$-ph) interactions and charge-density-wave (CDW) order in the bismuthate family of high-temperature superconductors remains unresolved. We address this question using nonperturbative hybrid Monte Carlo calculations for the parent compound BaBiO$_3$. Our model includes the Bi $6s$ and O $2p_σ$ orbitals and coupling to the Bi-O bond-stretching branch of optical phonons via modulations of the Bi-O hopping integral. We simulate three-dimensional clusters of up to 4000 orbitals, with input model parameters taken from {\it ab initio} electronic structure calculations and a phonon energy $\hbarΩ_0 = 60$~meV. Our results demonstrate that the coupling to the bond-stretching modes is sufficient to reproduce the CDW transition in this system, despite a relatively small dimensionless coupling. We also find that the transition deviates from the weak-coupling Peierls' picture. This work demonstrates that off-diagonal $e$-ph interactions in orbital space are vital in establishing the bismuthate phase diagram.
