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arXiv · 1108.2955

Josephson effect in a $CeCoIn_5$ microbridge

Oleksandr Foyevtsov·Fabrizio Porrati·Michael Huth
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Abstract

We report DC Josephson effects observed in a microbridge prepared from an individual crystalline growth domain of $CeCoIn_5$ thin film. Josephson effects were observed by periodic voltage modulations under external magnetic field $\Delta V(B)$ with the expected periodicity and by the temperature dependence of the Josephson critical current $I_c(T)$. The shape of $\Delta V(B)$ was found to be asymmetric, as it is expected for microbridges. The dependence $I_c(T)$ follows the Ambegaokar-Baratoff relation, which is unexpected for microbridges. Features in the dynamical resistance curves were attributed to the periodic motion of Abricosov vortices within the microbridge.

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Oleksandr Foyevtsov, Fabrizio Porrati, Michael Huth. 2011-08-15. Josephson effect in a $CeCoIn_5$ microbridge. https://doi.org/10.1016/j.physc.2012.04.009

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