AI 中文总结
研究双层哈伯德模型自能实频结构，用动态团簇近似。半填充时MI - BI转变涉及自能极点重排，掺杂时产生赝能隙并增强超导。序参量在MI - BI边界附近最大，极点可解释为费米子激发，\(t_{\perp}\)可控，为优化强关联超导提供平台。
AI 中文摘要
我们使用动态团簇近似研究双层哈伯德模型中自能的实频结构。在半填充时，莫特绝缘体 - 带绝缘体（MI - BI）转变涉及键合带和反键合带之间自能极点的重新排列；这些极点会随着层间跳跃\(t_{\perp}\)的变化而交叉。掺杂时，这种极点结构产生能带选择性赝能隙并增强\(s^{\pm}\)波超导性。序参量在MI - BI边界附近最大化，此时两个能带同时出现低能反常自能极点并协同增强配对。我们还表明这些自能极点可解释为涌现的费米子激发，提供了与单层哈伯德模型相同的增强配对机制。通过\(t_{\perp}\)对这些极点的可控性使双层系统成为优化强关联超导性的非常规平台。
英文摘要
We study the real-frequency structure of the self-energy in the bilayer Hubbard model, using the dynamical cluster approximation. At half filling, the Mott insulator-band insulator (MI-BI) crossover involves a rearrangement of self-energy poles between the bonding and antibonding bands; these poles cross as the interlayer hopping $t_{\perp}$ is varied. Upon doping, this pole structure produces a band-selective pseudogap and enhances $s^{\pm}$-wave superconductivity. The order parameter is maximized near the MI-BI boundary, where low-energy anomalous self-energy poles develop simultaneously in both bands and cooperatively enhance the pairing. We further show that these self-energy poles can be interpreted as emergent fermionic excitations, offering an enhanced-pairing mechanism in common with the single-layer Hubbard model. The controllability of these poles through $t_{\perp}$ makes the bilayer system an unconventional platform for optimizing strongly correlated superconductivity.
Comments6 pages, 4 figures; Supplemental Material: 7 pages, 7 figures, 2 tables
