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arXiv · 0804.2542

A supercurrent switch in graphene $π$-junctions

Jacob Linder·Takehito Yokoyama·Daniel Huertas-Hernando·Asle Sudbø
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Abstract

We study the supercurrent in a superconductor/ferromagnet/superconductor graphene junction. In contrast to its metallic counterpart, the oscillating critical current in our setup decays only weakly upon increasing exchange field and junction width. We find an unusually large residual value of the supercurrent at the oscillatory cusps due to a strong deviation from a sinusoidal current-phase relationship. Our findings suggest a very efficient device for dissipationless supercurrent switching.

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Jacob Linder, Takehito Yokoyama, Daniel Huertas-Hernando, Asle Sudbø. 2008-04-16. A supercurrent switch in graphene $π$-junctions. https://doi.org/10.1103/physrevlett.100.187004

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