论文标题
ca $ _3 $中的空间不均匀性和金属 - 绝缘体过渡（ru $ _ {1-x} $ ti $ _x $）$ _ 2 $ o $ $ _7 $
Spatial inhomogeneity and the metal-insulator transition in Ca$_3$(Ru$_{1-x}$Ti$_x$)$_2$O$_7$
论文作者
论文摘要
通过化学掺杂，将原始的莫特绝缘子变成相关的金属是强相关材料物理学的常见程序，例如基于高$ t_c $ cuprates的现象学。鲜苯甲酸双层化合物CA $ _3 $ ru $ _2 $ o $ _7 $是反向案例的一个突出例子，即在Stoichiemementry处使用相关的金属，可以通过TI掺杂实现过渡到绝缘状态的过渡。在这里，我们通过第一原则多体理论研究了这种令人困惑的金属绝缘体过渡（MIT），并阐明了RU Sublattice上电子相关性和对称性破坏之间的挑战性相互作用。虽然对CA $ _3 $ ru $ _2 $ o $ $ _7 $晶体结构的平均影响仍然相关，但MIT的关键是电子相关性与缺陷方面的空间不均匀性的合作。它们共同引起了现场选择性的Mott Critical和竞争轨道订购趋势的出现。
Turning a pristine Mott insulator into a correlated metal by chemical doping is a common procedure in strongly correlated materials physics, e.g. underlying the phenomenology of high-$T_c$ cuprates. The ruthenate bilayer compound Ca$_3$Ru$_2$O$_7$ is a prominent example of a reversed case, namely a correlated metal at stoichiometry that realizes a transition into an insulating state via Ti doping. We here investigate this puzzling metal-insulator transition (MIT) by first-principles many-body theory and elucidate a challenging interplay between electronic correlations and symmetry breakings on the Ru sublattice. While average effects on the Ca$_3$Ru$_2$O$_7$ crystal structure are still relevant, key to the MIT is the cooperation of electronic correlations with the spatial inhomogeneity in the defect regime. Together they give rise to the emergence of site-selective Mott criticality and competing orbital-ordering tendencies.
