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.
The newly discovered iron-chalcogenide superconductor KxFe2_ySe2 exhibits a distinct electronic structure from other iron-based su- perconductors. Exploiting polarization-dependent angle-resolved photoemission spectroscopy, we have determined the orbital char- acters of band structure in a KxFe2_ySe2 superconductor. To a large extent, we find that KxFe2_ySe2 superconductor 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 be- tween them. Moreover, in contrast to the band calculation results, the small electron pocket around Z is found to be mainly consisted of the dz2 orbital. The determined orbital characters would help to construct a realistic model for KxFe2_ySe2.
基金
supported in part by the National Natural Science Foundation of China,Ministry of Education of China
the National Basic Research Program of China (2012CB921400,2011CB921802 and 2011CBA00112)
