论文标题
$ GW $+EDMFT调查Pr $ _ {1-X} $ SR $ _X $ NIO $ _2 $在压力下
$GW$+EDMFT investigation of Pr$_{1-x}$Sr$_x$NiO$_2$ under pressure
论文作者
论文摘要
由于最近对PR $ _ {1-X} $ _ $ _x $ _x $ nio $ _2 $的$ T_C $对$ t_c $的大压力效应的实验性观察的激励，我们研究了该化合物的电子特性，这是$ x = 0 $的压力的函数，并使用自我cossistent $ gw $+gw $+edmft掺杂$ x = 0 $和$ 0.2 $。我们的数值结果表明，化学掺杂和物理压力之间存在非平凡的相互作用，以及轨道职业，局部水平能量和相互作用参数随压力增加而进行的较小但系统的变化。超出密度函数理论的适当处理相关效应在揭示这些趋势方面起着重要作用。虽然未凝结化合物的电子结构的压力依赖性变化表明在高压状态下具有更单一的样式行为，但在掺杂系统中发现了质量不同的行为。我们还指出，轨道职业和旋转状态的波动与单带图不一致，至少需要两个波段模型来重现全部结果。这种多轨本质在掺杂化合物中最清楚地表现出来。
Motivated by the recent experimental observation of a large pressure effect on $T_c$ in Pr$_{1-x}$Sr$_x$NiO$_2$, we study the electronic properties of this compound as a function of pressure for $x=0$ and $0.2$ doping using self-consistent $GW$+EDMFT. Our numerical results demonstrate a non-trivial interplay between chemical doping and physical pressure, and small but systematic changes in the orbital occupations, local level energies, and interaction parameters with increasing pressure. The proper treatment of correlation effects, beyond density function theory, is shown to play an important role in revealing these trends. While the pressure dependent changes in the electronic structure of the undoped compound suggest a more single-band-like behavior in the high-pressure regime, a qualitatively different behavior is found in the doped system. We also point out that the fluctuations in the orbital occupations and spin states are not consistent with a single-band picture, and that at least a two-band model is necessary to reproduce the full result. This multi-orbital nature manifests itself most clearly in the doped compound.
