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Excess current in superconducting Sr$_2$RuO$_4$

F. Laube·G. Goll·M. Eschrig·M. Fogelström·Ralph Werner
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Abstract

We present results from point-contact measurements on Sr$_2$RuO$_4$ that show a linear dependence of the excess current as a function of temperature and applied magnetic fields over a surprisingly wide range of the phase diagram. We propose an explanation of this finding in terms of a p-wave triplet-pairing state with coupling to a low-energy fluctuation mode. Within this model we obtain a quantitative description of the temperature dependence of the excess current. The impact of surface effects on order parameter and excess current is addressed.

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F. Laube, G. Goll, M. Eschrig, M. Fogelström, Ralph Werner. 2003-06-18. Excess current in superconducting Sr$_2$RuO$_4$. https://doi.org/10.1103/physrevb.69.014516

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