Inverse-photoemission spectroscopy of iron-based superconductors NdFeAsO sub(1-[delta]) and Ba(Fe sub(1-x)Co sub(x)) sub(2)As sub(2)

• Published in: Journal of physics. Conference series 2012-01, Vol.391, p.1-4
• Main Authors: Sato, H, Utsumi, Y, Morimoto, O, Nakashima, Y, Ino, A, Aiura, Y, Iyo, A, Kito, H, Miyazawa, K, Shirage, P M, Lee, C H, Kihou, K, Eisaki, H, Namatame, H, Taniguchi, M
• Format: Article
• Language: English
• Subjects: Electronic structure; Fermi level; Fermi surfaces; Neodymium; Spectroscopy; Superconductors; Three dimensional
• ISSN: 1742-6588; 1742-6596
• DOI: 10.1088/1742-6596/391/1/012137

Unoccupied electronic structure of iron-based superconductors NdFeAsO sub(0.7) (T sub(c)=51 K), BaFe sub(2)As sub(2) and Ba(Fe sub(0.89)Co sub(0.11)) sub(2)As sub(2) (T sub(c)=23 K) has been investigated by means of inverse-photoemission spectroscopy (IPES). The unoccupied Fe 3d states are observed around 1 cV above the Fermi level for all compounds. The Fe 3p-3d resonant IPES suggests that the unoccupied Fe 3d states of Ba(Fe sub(1-x)Co sub(x)) sub(2)As sub(2) have more localized character compared with those of NdFeAsO sub(0.7). The unoccupied Nd 4f states of NdFeAsO sub(0.7) are located around 5 and 7 eV, and the Ba 5d and Ba 4f states of Ba(Fe sub(1-x)Co sub(x)) sub(2)As sub(2) are located around 5 and 12 eV, respectively.