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arXiv · 1409.0152

Magnetic, electrical and structural properties of the new Re-doped ruthenocuprate Ru1-xRexSr2GdCu2Oy

Abstract

Despite the discovery of new superconductors classes, high-Tc oxides continue to be a current topic, because of their complex phase diagrams and doping-dependant effects (allowing one to investigate the interaction between orbitals), as well as structural properties such as lattice distortion and charge ordering, among many others. Ruthenocuprates are magnetic superconductors in which the magnetic transition temperature is much higher than the critical superconducting temperature, making them unique compounds. With the aim of investigating the dilution of the magnetic Ru sub-lattice, we proposed the synthesis of the new Ru1-xRexSr2GdCu2Oy ruthenocupratetype family, adapting the known two-step process (double perovskite + CuO)by directly doping the double perovskite, thus obtaining the new perovskite compound Sr2GdRu1-xRexOy, which represents a new synthesis process to the best of our knowledge. Our samples were structurally characterised through X-ray diffraction, and the patterns were analysed via Rietveld refinement. A complete magnetic characterisation as a function of temperature and applied field, as well as transport measurements were carried out. We discuss our results in the light of the two-lattice model for ruthenocuprates, and a relation between RuO2 (magnetic) and CuO2 (superconductor) sublattices can clearly be observed.

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BibTeXRIS

L. T. Corredor, J. Albino Aguiar, D. A. Landínez Téllez, P. Pureur, F. Mesquita, J. Roa-Rojas. 2014-08-30. Magnetic, electrical and structural properties of the new Re-doped ruthenocuprate Ru1-xRexSr2GdCu2Oy. https://arxiv.org/abs/1409.0152

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