发表机构
Graduate School of Engineering, Kyushu Institute of Technology; Department of Material Science, University of Hyogo; Institute for Materials Research (IMR), Tohoku University; International Quantum Materials Center (Q 2 ), Advanced Institute for Materials Research (WPI-AIMR), Tohoku University; Physics Division, Sophia University; RIKEN Center for Emergent Matter Science (CEMS); Department of Physics, The University of Tokyo（九州工业大学工学研究科; 兵库大学物质科学系; 东北大学材料科学研究所; 东北大学先进材料研究机构国际量子材料中心; 上智大学物理学部; 理化学研究所新兴物质科学中心; 东京大学物理学系）
机构由 AI 辅助整理，请以论文原文为准。AI 中文总结
本研究利用动力学顶点近似，在填充和层间跳跃参数空间中确定强关联双层Hubbard模型的超导景观，发现中间层间跳跃和适度掺杂可优化超导转变温度，且费米面畸变能进一步增强超导性。
AI 中文摘要
耦合两个强关联层为排斥驱动的超导开辟了一条独特途径。然而，层间耦合本身也使得超导性的优化变得高度非平凡。利用动力学顶点近似，我们确定了由填充和层间跳跃所张成的扩展参数空间中的超导景观。我们识别出一个最优区域，位于中间层间跳跃和远离半填充的适度掺杂处，在该区域系统表现出高超导转变温度（$T_{\rm c}$）并具有带间$s_{\pm}$波间隙结构。然而，在半填充附近，强的自能效应通过降低低能谱权重可以抑制超导趋势。我们进一步表明，由更长程跳跃引起的费米面畸变可以削弱这种抑制并增强$T_{\rm c}$。我们的结果确立了填充、层间跳跃和费米面几何如何共同优化强关联双层Hubbard模型中的超导区域。
英文摘要
Coupling two strongly correlated layers opens a distinct route to repulsion-driven superconductivity. Yet the same interlayer coupling makes the optimization of superconductivity highly nontrivial. Using the dynamical vertex approximation, we determine the superconducting landscape in the enlarged parameter space spanned by filling and interlayer hopping. We identify an optimal regime at intermediate interlayer hopping and moderate doping away from half filling, where the system exhibits high superconducting transition temperatures ($T_{\rm c}$) with an interband $s_{\pm}$-wave gap structure. Toward half filling, however, strong self-energy effects can suppress the superconducting tendency by reducing the low-energy spectral weight. We further show that a Fermi-surface distortion induced by longer-range hoppings can weaken this suppression and enhance $T_{\rm c}$. Our results establish how filling, interlayer hopping, and Fermi-surface geometry jointly optimize the superconducting regime in the strongly correlated bilayer Hubbard model.
Comments6+4 pages, 5+5 figures
