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arXiv · 0804.3188

Nonlinear magnetic response in ruthenocuprates

I. Zivkovic·V. P. S. Awana·H. Berger
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Abstract

We have performed an investigation of the nonlinear magnetic response in ruthenocuprates. A negative, diverging-like peak at the main magnetic transition T_N in RuSr2RECu2O8 (RE = Gd, Y) indicates a possible canted antiferromagnetic order. Another well defined feature above T_N points to a blocking of superparamagnetic particles through the T^(-3) dependence of the third harmonic at higher temperatures. Below T_N a nondiverging peak appears, which is strongly affected by the addition of 10% of Cu ions in the RuO2 planes. In RuSr2RE(2-x)Ce(x)Cu2O10 the main magnetic transition T_M is accompanied by two characteristic temperatures in the third harmonic of the ac susceptibility, in agreement with recent studies from uSR and Mossbauer spectroscopy. We find that the spin-spin correlation temperature is the same in both families of ruthenocuprates.

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I. Zivkovic, V. P. S. Awana, H. Berger. 2008-04-20. Nonlinear magnetic response in ruthenocuprates. https://doi.org/10.1140/epjb/e2008-00188-7

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