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Tuning of the superconducting and ferromagnetic transitions by Cu doping for Ru in GdSr2RuCu2O8

J. Janaki·T. Geetha Kumary·R. Nagarajan·T. A. Mary·M. C. Valsakumar·V. S. Sastry·Y. Hariharan·T. S. Radhakrishnan
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Abstract

In order to explore the possibility of tuning superconducting and ferromagnetic transitions by Cu doping (for Ru) in GdSr2RuCu2O8, we have carried out synthesis and characterization of GdSr2Ru{1-x}Cu{2+x)O8 (x = 0, 0.05, 0.1, 0.2) and studied their physical properties. Coexistence of superconductivity and ferromagnetism is observed in all the Cu doped samples studied here. The zero field susceptibility data suggests formation of a spontaneous vortex phase. Cu doping decreases the ferromagnetic Curie temperature, whereas the superconducting transition temperature increases until an optimal concentration x~0.1. This reflects an increase in hole transfer to the CuO2 planes and reduction of ferromagnetic order within the ruthenate layers.

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J. Janaki, T. Geetha Kumary, R. Nagarajan, T. A. Mary, M. C. Valsakumar, V. S. Sastry, Y. Hariharan, T. S. Radhakrishnan. 2003-03-15. Tuning of the superconducting and ferromagnetic transitions by Cu doping for Ru in GdSr2RuCu2O8. https://arxiv.org/abs/cond-mat/0303287

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