论文标题
在压力下的顺磁性FEO中的光发射光谱：朝\ textit {ab-initio}描述
Photoemission spectrum in paramagnetic FeO under pressure: towards an \textit{ab-initio} description
论文作者
论文摘要
在这项工作中，我们使用我们最近衍生的多体有效能理论（MEGE）的精制版本在压力下对副磁性FEO的光发射光谱进行了详尽的研究。我们表明，在非磁性阶段的非磁性描述中，这次聚会总体描述了在环境压力下的光发射光谱以及通过增加压力所经历的变化。 In particular at ambient pressure the band gap opens between the mixed Fe $t_{2g}$ and O $2p$ states and the Fe 4s states and, moreover, a $d$-$d$ gap opens, which is compatible with a high-spin configuration (hence nonzero local magnetic moments as observed in experiment), whereas decreasing pressure the band gap tends to close, $t_{2g}$ states tend to become完全占用和$ e_ {g} $完全没有占用，这与低自旋构型兼容（因此在实验中观察到的磁矩崩溃）。这是一个了不起的结果，因为在非磁相的非磁性描述中，比赛能够正确描述光发射频谱和周围和高压下的旋转构型。为了进行比较，我们报告了使用密度功能理论获得的带有杂交功能的筛选交换（HSE06）和$ GW $方法（自洽的cohsex）的带隙值，这些变体对于描述了反铁磁相。两种方法都在环境压力下打开差距，尽管通过构造，它们具有低自旋构型。他们正确地描述了带隙截止的压力增加。我们还报告了在LDA上以一击完全动力的$ GW $获得的金属相的光发射光谱，该频谱与文献产生的DMFT非常相似。
In this work we provide an exhaustive study of the photemission spectrum of paramagnetic FeO under pressure using a refined version of our recently derived many-body effective energy theory (MEET). We show that, within a nonmagnetic description of the paramagnetic phase, the MEET gives an overall good description of the photoemission spectrum at ambient pressure as well as the changes it undergoes by increasing pressure. In particular at ambient pressure the band gap opens between the mixed Fe $t_{2g}$ and O $2p$ states and the Fe 4s states and, moreover, a $d$-$d$ gap opens, which is compatible with a high-spin configuration (hence nonzero local magnetic moments as observed in experiment), whereas decreasing pressure the band gap tends to close, $t_{2g}$ states tend to become fully occupied and $e_{g}$ fully unoccupied, which is compatible with a low-spin configuration (hence a collapse of the magnetic moments as observed in experiment). This is a remarkable result, since, within a nonmagnetic description of the paramagnetic phase, the MEET is capable to correctly describe the photoemission spectrum and the spin configuration at ambient as well as high pressure. For comparison we report the band gap values obtained using density-functional theory with a hybrid functional containing screened exchange (HSE06) and a variant of the $GW$ method (self-consistent COHSEX), which are reliable for the description of the antiferromagnetic phase. Both methods open a gap at ambient pressure, although, by construction, they give a low-spin configuration; increasing pressure they correctly describes the band gap closing. We also report the photoemission spectrum of the metallic phase obtained with one-shot fully-dynamical $GW$ on top of LDA, which gives a spectrum very similar to DMFT results from literature.
