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Thermodynamic Properties of (Ca,Sr)$_2$RuO$_4$ in Magnetic Fields

J. Baier·T. Zabel·M. Kriener·P. Steffens·O. Schumann·O. Friedt·A. Freimuth·A. Revcolevschi·S. Nakatsuji·Y. Maeno·T. Lorenz·M. Braden
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Abstract

We have studied the influence of a magnetic field on the thermodynamic properties of Ca$_{2-x}$Sr$_{x}$RuO$_4$ in the intermediate metallic region with tilt and rotational distortions ($0.2\leq x \leq 0.5$). We find strong and anisotropic thermal expansion anomalies at low temperatures, which are suppressed and even reversed by a magnetic field. The metamagnetic transition of Ca$_{1.8}$Sr$_{0.2}$RuO$_4$ is accompanied by a large magnetostriction. Furthermore, we observe a strong magnetic-field dependence of $c_p/T$, that can be explained by magnetic fluctuations.

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J. Baier, T. Zabel, M. Kriener, P. Steffens, O. Schumann, O. Friedt, A. Freimuth, A. Revcolevschi, S. Nakatsuji, Y. Maeno, T. Lorenz, M. Braden. 2005-11-09. Thermodynamic Properties of (Ca,Sr)$_2$RuO$_4$ in Magnetic Fields. https://doi.org/10.1016/j.physb.2006.01.215

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