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arXiv · 1011.2056

Quasi-Two-Dimensional Fermi Surfaces and Coherent Interlayer Transport in KFe$_2$As$_2$

M. Kimata·T. Terashima·N. Kurita·H. Satsukawa·A. Harada·K. Kodama·A. Sato·M. Imai·K. Kihou·C. H. Lee·H. Kito·H. Eisaki·A. Iyo·T. Saito·H. Fukazawa·Y. Kohori·H. Harima·S. Uji
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Abstract

We report the results of the angular-dependent magnetoresistance oscillations (AMROs), which can determine the shape of bulk Fermi surfaces in quasi-two-dimensional (Q2D) systems, in a highly hole-doped Fe-based superconductor KFe$_2$As$_2$ with $T_c \approx$ 3.7 K. From the AMROs, we determined the two Q2D FSs with rounded-square cross sections, corresponding to 12% and 17% of the first Brillouin zone. The rounded-squared shape of the FS cross section is also confirmed by the analyses of the interlayer transport under in-plane fields. From the obtained FS shape, we infer the character of the 3d orbitals that contribute to the FSs.

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M. Kimata, T. Terashima, N. Kurita, H. Satsukawa, A. Harada, K. Kodama, A. Sato, M. Imai, K. Kihou, C. H. Lee, H. Kito, H. Eisaki, A. Iyo, T. Saito, H. Fukazawa, Y. Kohori, H. Harima, S. Uji. 2010-11-09. Quasi-Two-Dimensional Fermi Surfaces and Coherent Interlayer Transport in KFe$_2$As$_2$. https://doi.org/10.1103/physrevlett.105.246403

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