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arXiv · 1404.1095

Fermi-Surface Reconstruction and Complex Phase Equilibria in CaFe$_{2}$As$_{2}$

K. Gofryk·B. Saparov·T. Durakiewicz·A. Chikina·S. Danzenbächer·D. V. Vyalikh·M. J. Graf·A. S. Sefat
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Abstract

Fermi-surface topology governs the relationship between magnetism and superconductivity in iron-based materials. Using low-temperature transport, angle-resolved photoemission, and x-ray diffraction we show unambiguous evidence of large Fermi surface reconstruction in CaFe$_{2}$As$_{2}$ at magnetic spin-density-wave and nonmagnetic collapsed-tetragonal ($cT$) transitions. For the $cT$ transition, the change in the Fermi surface topology has a different character with no contribution from the hole part of the Fermi surface. In addition, the results suggest that the pressure effect in CaFe$_{2}$As$_{2}$ is mainly leading to a rigid-band-like change of the valence electronic structure. We discuss these results and their implications for magnetism and superconductivity in this material.

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K. Gofryk, B. Saparov, T. Durakiewicz, A. Chikina, S. Danzenbächer, D. V. Vyalikh, M. J. Graf, A. S. Sefat. 2014-04-03. Fermi-Surface Reconstruction and Complex Phase Equilibria in CaFe$_{2}$As$_{2}$. https://doi.org/10.1103/physrevlett.112.186401

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