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arXiv · 1202.5956

Nanoscale textured superconductivity in Ru-substituted BaFe2As2 : a challenge to a universal phase diagram for the pnictides

Yannis Laplace·Julien Bobroff·Veronique Brouet·Gaston Collin·Florence Rullier-Albenque·Dorothee Colson·Anne Forget
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Abstract

75As NMR experiments were performed in Ba(Fe1-xRux)2As2 for x=0 to 80%. Magnetic fractions and NMR lineshapes demonstrate that Ru substitution destroys the antiferromagnetic (AF) order inhomogeneously with a magnetic moment distributed from 0.9 to 0 uB. Superconductivity emerges at intermediate Ru doping and coexists with AF order only in the regions where moments are smaller than ~0.3uB, resulting in an original nanoscale texture. This situation contrasts with that of Co substitution, challenging the apparent universality of the phase diagram in Fe-based superconductors.

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Yannis Laplace, Julien Bobroff, Veronique Brouet, Gaston Collin, Florence Rullier-Albenque, Dorothee Colson, Anne Forget. 2012-02-27. Nanoscale textured superconductivity in Ru-substituted BaFe2As2 : a challenge to a universal phase diagram for the pnictides. https://doi.org/10.1103/physrevb.86.020510

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