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Superconductivity-induced re-entrance of the orthorhombic distortion in Ba1-xKxFe2As2.

ABSTRACT: Detailed knowledge of the phase diagram and the nature of the competing magnetic and superconducting phases is imperative for a deeper understanding of the physics of iron-based superconductivity. Magnetism in the iron-based superconductors is usually a stripe-type spin-density-wave, which breaks the tetragonal symmetry of the lattice, and is known to compete strongly with superconductivity. Recently, it was found that in some systems an additional spin-density-wave transition occurs, which restores this tetragonal symmetry, however, its interaction with superconductivity remains unclear. Here, using thermodynamic measurements on Ba1-xKxFe2As2 single crystals, we show that the spin-density-wave phase of tetragonal symmetry competes much stronger with superconductivity than the stripe-type spin-density-wave phase, which results in a novel re-entrance of the latter at or slightly below the superconducting transition.

SUBMITTER: Bohmer AE

PROVIDER: S-EPMC4532874 | biostudies-literature | 2015 Jul

REPOSITORIES: biostudies-literature

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Superconductivity-induced re-entrance of the orthorhombic distortion in Ba1-xKxFe2As2.

Böhmer A E AE Hardy F F Wang L L Wolf T T Schweiss P P Meingast C C

Nature communications 20150731

Detailed knowledge of the phase diagram and the nature of the competing magnetic and superconducting phases is imperative for a deeper understanding of the physics of iron-based superconductivity. Magnetism in the iron-based superconductors is usually a stripe-type spin-density-wave, which breaks the tetragonal symmetry of the lattice, and is known to compete strongly with superconductivity. Recently, it was found that in some systems an additional spin-density-wave transition occurs, which rest ...[more]

PMID: 26227915

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