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arXiv · 1401.4403

Fermi Surface of KFe$_2$As$_2$ from Quantum Oscillations in Magnetostriction

D. A. Zocco·K. Grube·F. Eilers·T. Wolf·H. v. Löhneysen
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Abstract

We present a study of the Fermi surface of KFe$_2$As$_2$ single crystals. Quantum oscillations were observed in magnetostriction measured down to 50 mK and in magnetic fields $H$ up to 14 T. For $H \parallel c$, the calculated effective masses are in agreement with recent de Haas-van Alphen and ARPES experiments, showing enhanced values with respect to the ones obtained from previous band calculations. For $H \parallel a$, we observed a small orbit at a cyclotron frequency of 64 T, characterized by an effective mass of $\sim 0.8 m_e$, supporting the presence of a three-dimensional pocket at the Z-point.

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D. A. Zocco, K. Grube, F. Eilers, T. Wolf, H. v. Löhneysen. 2014-01-17. Fermi Surface of KFe$_2$As$_2$ from Quantum Oscillations in Magnetostriction. https://doi.org/10.7566/jpscp.3.015007

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