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arXiv · 1103.3329

Complete Fermi surface in BaFe$_2$As$_2$ observed via Shubnikov-de Haas oscillation measurements on detwinned single crystals

Taichi Terashima·Nobuyuki Kurita·Megumi Tomita·Kunihiro Kihou·Chul-Ho Lee·Yasuhide Tomioka·Toshimitsu Ito·Akira Iyo·Hiroshi Eisaki·Tian Liang·Masamichi Nakajima·Shigeyuki Ishida·Shin-ichi Uchida·Hisatomo Harima·Shinya Uji
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Abstract

We show that the Fermi surface (FS) in the antiferromagnetic phase of BaFe$_2$As$_2$ is composed of one hole and two electron pockets, all of which are three dimensional and closed, in sharp contrast to the FS observed by angle-resolved photoemission spectroscopy. Considerations on the carrier compensation and Sommerfeld coefficient rule out existence of unobserved FS pockets of significant sizes. A standard band structure calculation reasonably accounts for the observed FS, despite the overestimated ordered moment. The mass enhancement, the ratio of the effective mass to the band mass, is 2--3.

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Taichi Terashima, Nobuyuki Kurita, Megumi Tomita, Kunihiro Kihou, Chul-Ho Lee, Yasuhide Tomioka, Toshimitsu Ito, Akira Iyo, Hiroshi Eisaki, Tian Liang, Masamichi Nakajima, Shigeyuki Ishida, Shin-ichi Uchida, Hisatomo Harima, Shinya Uji. 2011-10-18. Complete Fermi surface in BaFe$_2$As$_2$ observed via Shubnikov-de Haas oscillation measurements on detwinned single crystals. https://doi.org/10.1103/physrevlett.107.176402

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