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Register a new userJosephson effect in $CeCoIn_5$ microbridges as seen via quantum interferometry
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Added by
Oleksandr Foyevtsov
Publication date
2011
fields
Physics
and research's language is
English
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A superconducting quantum interference device (SQUID) was prepared on a micron-sized single crystal using a selected growth domain of a thin film of $CeCoIn_5$ grown by molecular beam epitaxy. SQUID voltage oscillations of good quality were obtained as well as interference effects stemming from the individual Josephson microbridges. The transport characteristics in the superconducting state exhibited several peculiarities which we ascribe to the periodic motion of vortices in the microbridges. The temperature dependence of the Josephson critical current shows good correspondence to the Ambegaokar-Baratoff relation, expected for the ideal Josephson junction. The results indicate a promising pathway to identify the type of order parameter in $CeCoIn_5$ by means of phase-sensitive measurements on microbridges.
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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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