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arXiv · 0907.3429

Coexistence of incommensurate magnetism and superconductivity in Fe_{1+y}Se_xTe_{1-x}

R. Khasanov·M. Bendele·A. Amato·P. Babkevich·A. T. Boothroyd·A. Cervellino·K. Conder·S. N. Gvasaliya·H. Keller·H. -H. Klauss·H. Luetkens·E. Pomjakushina·B. Roessli
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Abstract

We report an investigation into the superconducting and magnetic properties of Fe_{1+y}Se_{x}Te_{1-x} single crystals by magnetic susceptibility, muon spin rotation, and neutron diffraction. We find three regimes of behavior in the phase diagram for 0\leq x\leq 0.5: (i) commensurate magnetic order for x< 0.1, (ii) bulk superconductivity for $x\lesssim 0.1$, and (iii) a range \sim 0.25\leq x\leq 0.45 in which superconductivity coexists with static incommensurate magnetic order. The results are qualitatively consistent with a two-band mean-field model in which itinerant magnetism and extended s-wave superconductivity are competing order parameters.

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R. Khasanov, M. Bendele, A. Amato, P. Babkevich, A. T. Boothroyd, A. Cervellino, K. Conder, S. N. Gvasaliya, H. Keller, H. -H. Klauss, H. Luetkens, E. Pomjakushina, B. Roessli. 2009-07-20. Coexistence of incommensurate magnetism and superconductivity in Fe_{1+y}Se_xTe_{1-x}. https://doi.org/10.1103/physrevb.80.140511

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