The electronic phase diagram of the LaO<SUB>1‑x</SUB>F<SUB>x</SUB>FeAs superconductor

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• Klauss, H. -H.
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• Kraken, M.
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• Litterst, F. J.
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• Dellmann, T.
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• Klingeler, R.
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• Hess, C.
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• Khasanov, R.
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• Amato, A.
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• Baines, C.
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• Kosmala, M.
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• Schumann, O. J.
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• Braden, M.
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• Hamann-Borrero, J.
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• Leps, N.
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• Kondrat, A.
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• Behr, G.
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• Werner, J.
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• Büchner, B.

Abstract

In non-conventional superconductors, it is usually found that superconductivity emerges in the vicinity of a critical point where antiferromagnetic order gradually disappears—corresponding to a second-order transition. Investigation of the newly discovered iron pnictide superconductors challenges this picture, showing an abrupt, first-order transition.