Origin of superconductivity in hole doped SrBiO_(3) bismuth oxide perovskite from parameter-free first-principles simulations  

作　　者：Julien Varignon 

机构地区：[1]Laboratoire CRISMAT,CNRS UMR 6508,ENSICAEN,Normandie Université,6 boulevard Maréchal Juin,F-14050,Caen Cedex 4,France

出　　处：《npj Computational Materials》2023年第1期2044-2052,共9页计算材料学（英文）

摘　　要：The recent discovery of nickel oxide superconductors have highlighted the importance of first-principles simulations forunderstanding the formation of the bound electrons at the core of superconductivity. Nevertheless, superconductivity in oxides isoften 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, Sr_(1-x)K_(x)BiO_(3) superconductors form an ideal testbed forunveiling the lowest theory level needed to model complex superconductors and the underlying pairing mechanism yieldingsuperconductivity. Here I show that parameter-free DFT simulations capture all the experimental features and related quantities of Sr_(1-x)K_(x)BiO_(3) superconductors, encompassing the prediction of an insulating to metal phase transition upon increasing the K dopingcontent and of an electron-phonon coupling constant of 1.22 in sharp agreement with the experimental value of 1.3 ± 0.2. Theproximity of a disproportionated phase is further demonstrated to be a prerequisite for superconductivity in bismuthates.

关 键 词：SUPERCONDUCTIVITY BISMUTH parameter 

分 类 号：TM26[一般工业技术—材料科学与工程]