The newly discovered iron-chalcogenide superconductorKxFe2ySe2exhibits a distinct electronic structure from other iron-based superconductors.Exploiting polarization-dependent angle-resolved photoemission spectroscopy,...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.展开更多
基金supported in part by the National Natural Science Foundation of China,Ministry of Education of Chinathe National Basic Research Program of China (2012CB921400,2011CB921802 and 2011CBA00112)
文摘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.