论文标题
孔掺杂srbio3二氧化物氧化物钙钛矿中超导性的起源来自无参数的第一原理模拟
Origin of superconductivity in hole doped SrBiO3 bismuth oxide perovskite from parameter-free first-principles simulations
论文作者
论文摘要
最近的发现镍氧化物超导体强调了第一原理模拟对理解超导性核心的结合电子形成的重要性。然而，氧化物中的超导性通常归因于密度功能理论（DFT）无法正确考虑的强电子相关效应，从而取消了此技术的资格。 SR1-XKXBIO3超导体是等氧化物到镍氧化物的，构成了揭幕的理想测试床（i）对复杂超导体进行建模所需的最低理论水平以及（ii）产生超导性的基本配对机制。在这里，我表明，无参数的DFT模拟捕获了SR1-XKXBIO3超导体的所有实验特征和相关数量，其中包括预测在增加k掺杂含量的绝缘金属相变的绝缘，并增加了电子 - phonon耦合常数为1.22的1.22均匀均匀的实验值1.3 +/-0.2 +/-0.2 +/-0.2。进一步证明，不成比例的阶段的接近性是在偶氮室中超导性的先决条件。这项工作强调了适当执行的DFT是研究复杂氧化物中超导性的足够平台。
The recent discovery nickel oxides superconductors have highlighted the importance of first-principles simulations for understanding the formation of the bound electrons at the core of superconductivity. Nevertheless, superconductivity in oxides is often ascribed to strong electronic correlation effects that Density Functional Theory (DFT) cannot properly take into account, thereby disqualifying this technique. Being isostructural to nickel oxides, Sr1-xKxBiO3 superconductors form an ideal testbed for unveiling (i) the lowest theory level needed to model complex superconductors and (ii) the underlying pairing mechanism yielding superconductivity. Here I show that parameter-free DFT simulations capture all the experimental features and related quantities of Sr1-xKxBiO3 superconductors, encompassing the prediction of an insulating to metal phase transition upon increasing the K doping content and of an electron-phonon coupling constant of 1.22 in sharp agreement with the experimental value of 1.3 +/- 0.2. Proximity of a disproportionated phase is further demonstrated to be a prerequisite for superconductivity in bismuthates. This work highlights that appropriately executed DFT is a sufficient platform for studying superconductivity in complex oxides.
