The orbital characters of low-energy electronic structure in iron-chalcogenide superconductor K_xFe_(2-y)Se_2

• 来源期刊: 科学通报(英文版)
• 学科: 化学
• 年，卷（期）: 2012,（30）
• 页码范围: 3829-3835
• 页数: 7页
• 分类号: O611.3
• 语种: 中文

摘要

The newly discovered iron-chalcogenide superconductorKxFe2ySe2exhibits a distinct electronic structure from other iron-based superconductors.Exploiting polarization-dependent angle-resolved photoemission spectroscopy,we have determined the orbital characters of band structure in aKxFe2ySe2superconductor.To a large extent,we find thatKxFe2ySe2superconductor shares similar orbital characters with other iron-based superconductors,but with its own characteristics.For example,we have resolved two highly degenerate electron cylinders around the zone corner in the s and p geometries,respectively,indicating negligible interactions between them.Moreover,in contrast to the band calculation results,the small electron pocket around Z is found to be mainly consisted of the d z 2 orbital.The determined orbital characters would help to construct a realistic model forKxFe2ySe2.