发表机构
State Key Laboratory of Low-Dimensional Quantum Physics, Department of Physics, Tsinghua University; Frontier Science Center for Quantum Information; Department of Materials Science and Engineering, University of Utah; School of Physics, Beihang University; Beijing Academy of Quantum Information Sciences; Southern University of Science and Technology; Hefei National Laboratory（清华大学物理系低维量子物理国家重点实验室; 量子信息前沿科学中心; 犹他大学材料科学与工程系; 北京航空航天大学物理学院; 北京量子信息科学研究院; 南方科技大学; 合肥国家实验室）
机构由 AI 辅助整理，请以论文原文为准。AI 中文总结
该研究发现铁基超导体中费米能级下方的深dz2能带可增强超导配对强度，通过扫描隧道显微镜调控晶格实现能带杂化，证实能带杂化是优化超导材料的有效机制。
AI 中文摘要
铁基超导电性的传统认识通常基于费米能级处的电子能带，而更深的能带被忽视作为潜在因素。本文拓展了这一观点，证明费米能级下方的深dz2能带可用于增强超导配对强度。通过扫描隧道显微镜机械改变铁基超导体的晶格，我们观察到深dz2能带相关特征向上移动，导致其与费米能级处的主要超导能带杂化。我们通过准粒子干涉成像可视化了这种能带杂化及由此产生的增强超导能隙的新证据，提供了确凿证据：调控深能带与配对活性能带之间的关联是放大超导能隙的有效机制。本研究完善了与配对相关的电子结构的传统观点，并确立能带杂化是优化超导材料的有效途径。
英文摘要
Conventional understanding of iron-based superconductivity is usually established based on electronic bands at the Fermi level, leaving deeper bands overlooked as potential factor. Here, we expand this view by demonstrating that a deep-lying dz2 band below the Fermi level can be employed to enhance the superconducting paring strength. By using scanning tunneling microscope to mechanically change the crystal lattice of an iron-based superconductor, we observe an upward shift of the deep-lying dz2 band related feature, leading to hybridization with the primary superconducting bands at the Fermi level. We visualize the novel evidence of this band hybridization and resulting enhanced superconducting gap through quasiparticle interference imaging, providing conclusive evidence that engineering such correlations between deep and pairing-active bands is a potent mechanism for amplifying the superconducting gap. This work refines the conventional view of pairing-relevant electronic structures and establishes band hybridization as an effective way to optimize superconducting materials.
Comments12 pages, 5 figures
