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Ruthenocuprates: Intrinsic magnetic multilayers

I. Zivkovic·Y. Hirai·M. Prester·D. Drobac·D. Ariosa·G. Margaritondo·I. Felner·B. H. Frazer·M. Onellion
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Abstract

We report ac susceptibility measurements on polycrystalline samples of SrRuO_3 and three ruthenocuprates: superconducting RuSr_2GdCu_2O_8 (Ru-1212), superconducting RuSr_2Eu_(2-x)Ce_xCu_2O_y (Ru-1222, x=0.5) and nonsuperconducting, insulating RuSr_2Eu_(2-x)Ce_xCu_2O_z (Ru-1222, x=1.0). Ac susceptibility of both Ru-1222 compositions exhibit logarithmic time relaxation and `inverted' hysteresis loops. Ru-1212 samples exhibit none of these behaviors. We interpret the magnetic behavior of Ru-1222 in the framework of weakly coupled magnetic multilayers and argue that superconductivity coexists with qualitatively different magnetic behaviors.

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I. Zivkovic, Y. Hirai, M. Prester, D. Drobac, D. Ariosa, G. Margaritondo, I. Felner, B. H. Frazer, M. Onellion. 2001-07-19. Ruthenocuprates: Intrinsic magnetic multilayers. https://arxiv.org/abs/cond-mat/0107388

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