论文标题
四面体几何设计中未掺杂的BAFE2AS2的超导性
Superconductivity in Undoped BaFe2As2 by Tetrahedral Geometry Design
论文作者
论文摘要
基于Fe的超导体在电荷，轨道和磁顺序1-4之间表现出不同的相互作用。原子几何形状的变化会影响Fe Atoms5,6和Fermi表面拓扑之间的电子跳跃，从而通过轨道重叠和占领的变化来影响磁挫败感和配对机制7-11。在这里，我们在实验上展示了一种系统的方法，可以在BAFE2AS2中使用化学掺杂，在外延异质结构中采用几何设计，而无需化学掺杂。我们通过超级晶格工程控制BAFE2AS2中的四方和正栓性，当AS-FE-AS AS AS接近常规的四面体接近时，我们在实验上发现它会诱导超导性。这种超晶格设计的方法可能会导致对基于Fe的超导体的低维超导性的见解。
Fe-based superconductors exhibit a diverse interplay between charge, orbital, and magnetic ordering1-4. Variations in atomic geometry affect electron hopping between Fe atoms5,6 and the Fermi surface topology, influencing magnetic frustration and the pairing mechanism through changes of orbital overlap and occupancies7-11. Here, we experimentally demonstrate a systematic approach to realize superconductivity without chemical doping in BaFe2As2, employing geometric design within an epitaxial heterostructure. We control both tetragonality and orthorhombicity in BaFe2As2 through superlattice engineering, which we experimentally find to induce superconductivity when the As-Fe-As bond angle approaches that in a regular tetrahedron. This approach of superlattice design could lead to insights into low dimensional superconductivity in Fe-based superconductors.
