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arXiv · 1108.4307

Microscopic co-existence of superconductivity and magnetism in Ba1-xKxFe2As2

Erwin Wiesenmayer·Hubertus Luetkens·Gwendolyne Pascua·Rustem Khasanov·Alex Amato·Heidi Potts·Benjamin Banusch·Hans-Henning Klauss·Dirk Johrendt
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Abstract

It is widely believed that, in contrast to its electron doped counterparts, the hole doped compound Ba1-xKxFe2As2 exhibits a mesoscopic phase separation of magnetism and superconductivity in the underdoped region of the phase diagram. Here, we report a combined high-resolution x-ray powder diffraction and volume sensitive muon spin rotation study of underdoped Ba1-xKxFe2As2 (0 \leq x \leq 0.25) showing that this paradigm is wrong. Instead we find a microscopic coexistence of the two forms of order. A competition of magnetism and superconductivity is evident from a significant reduction of the magnetic moment and a concomitant decrease of the magneto-elastically coupled orthorhombic lattice distortion below the superconducting phase transition.

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Erwin Wiesenmayer, Hubertus Luetkens, Gwendolyne Pascua, Rustem Khasanov, Alex Amato, Heidi Potts, Benjamin Banusch, Hans-Henning Klauss, Dirk Johrendt. 2011-08-22. Microscopic co-existence of superconductivity and magnetism in Ba1-xKxFe2As2. https://doi.org/10.1103/physrevlett.107.237001

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