Three-dimensional electronic structure of superconducting iron pnictides observed by angle-resolved photoemission spectroscopy

Walid Malaeb; Teppei Yoshida; Atsushi Fujimori; Masato Kubota; Kanta Ono; Kunihiro Kihou; Parasharam M. Shirage; Hijiri Kito; Akira Iyo; Hiroshi Eisaki; Yasuyuki Nakajima; Tsuyoshi Tamegai; Ryotaro Arita

doi:10.1143/jpsj.78.123706

arXiv · 0906.1846

Three-dimensional electronic structure of superconducting iron pnictides observed by angle-resolved photoemission spectroscopy

Walid Malaeb·Teppei Yoshida·Atsushi Fujimori·Masato Kubota·Kanta Ono·Kunihiro Kihou·Parasharam M. Shirage·Hijiri Kito·Akira Iyo·Hiroshi Eisaki·Yasuyuki Nakajima·Tsuyoshi Tamegai·Ryotaro Arita

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Abstract

We have performed an angle-resolved photoemission spectroscopy (ARPES) study of the undoped and electron-doped iron pnictides BaFe2\_{-x}CoxAs2 (Ba122) (x=0, 0.14) and studied the Fermi surfaces (FSs) and band dispersions near the Fermi level. The FS sheets we observed are consistent with the shrinkage of the hole-like pockets around the Brillouin Zone (BZ) center and the expansion of the electron pockets around the BZ corner in the electron-doped compound as compared to the undoped parent compound. Band dispersions and FSs around the BZ center strongly depend on the photon energy, indicating the three-dimensional (3D) electronic structure. This observation suggests that the antiferromagnetism and superconductivity in the pnictides may have to be considered including the orbital-dependent 3D electronic structure, where FS nesting is not necessarily strong.

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Walid Malaeb, Teppei Yoshida, Atsushi Fujimori, Masato Kubota, Kanta Ono, Kunihiro Kihou, Parasharam M. Shirage, Hijiri Kito, Akira Iyo, Hiroshi Eisaki, Yasuyuki Nakajima, Tsuyoshi Tamegai, Ryotaro Arita. 2009-06-10. Three-dimensional electronic structure of superconducting iron pnictides observed by angle-resolved photoemission spectroscopy. https://doi.org/10.1143/jpsj.78.123706

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