"Electronic structure of the BaFe2As2 family of iron-pnictide superconductors"

M. Yi: D. H. Lu, J. G. Analytis, J.-H. Chu, S.-K. Mo, R.-H. He, R. G. Moore, X. J. Zhou, G. F. Chen, J. L. Luo, N. L. Wang, Z. Hussain, D. J. Singh, I. R. Fisher, and Z.-X. Shen; Physical Review B, 07/24/09.

Additional Authors: D. H. Lu, J. G. Analytis, J.-H. Chu, S.-K. Mo, R.-H. He, R. G. Moore, X. J. Zhou, G. F. Chen, J. L. Luo, N. L. Wang, Z. Hussain, D. J. Singh, I. R. Fisher, and Z.-X. Shen

Abstract:

We use high-resolution angle-resolved photoemission to study the electronic structure of the BaFe2As2 pnictides. We observe two electron bands and two hole bands near the X point, (π,π) of the Brillouin zone, in the paramagnetic state for electron-doped Ba(Co0.06Fe0.94)2As2, undoped BaFe2As2, and hole-doped Ba0.6K0.4Fe2As2. Among these bands, only the electron bands cross the Fermi level, forming two electron pockets around X while the hole bands approach but never reach the Fermi level. We show that the band structure of the BaFe2As2 family matches reasonably well with the prediction of local-density approximation calculations after a momentum-dependent shift and renormalization. Our finding resolves a number of inconsistencies regarding the electronic structure of pnictides.