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arXiv · 1402.2412

Quantum Oscillations in EuFe2As2 single crystals

P. F. S. Rosa·B. Zeng·C. Adriano·T. M. Garitezi·T. Grant·Z. Fisk·L. Balicas·R. R. Urbano·P. G. Pagliuso
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Abstract

Quantum oscillation measurements can provide important information about the Fermi surface (FS) properties of strongly correlated metals. Here, we report a Shubnikov-de Haas (SdH) effect study on the pnictide parent compounds EuFe$_{2}$As$_{2}$ (Eu122) and BaFe$_{2}$As$_{2}$ (Ba122) grown by In-flux. Although both members are isovalent compounds with approximately the same density of states at the Fermi level, our results reveal subtle changes in their fermiology. Eu122 displays a complex pattern in the Fourier spectrum, with band splitting, magnetic breakdown orbits, and effective masses sistematically larger when compared to Ba122, indicating that the former is a more correlated metal. Moreover, the observed pockets in Eu122 are more isotropic and 3D-like, suggesting an equal contribution from the Fe $3d$ orbitals to the FS. We speculate that these FS changes may be responsible for the higher spin-density wave ordering temperature in Eu122.

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P. F. S. Rosa, B. Zeng, C. Adriano, T. M. Garitezi, T. Grant, Z. Fisk, L. Balicas, R. R. Urbano, P. G. Pagliuso. 2014-02-11. Quantum Oscillations in EuFe2As2 single crystals. https://doi.org/10.1103/physrevb.90.195146

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