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arXiv · 1607.07717

Tunable $\varphi$ Josephson Junction ratchet

R. Menditto·H. Sickinger·M. Weides·H. Kohlstedt·D. Koelle·R. Kleiner·E. Goldobin
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Abstract

We demonstrate experimentally the operation of a deterministic Josephson ratchet with tunable asymmetry. The ratchet is based on a $\varphi$ Josephson junction with a ferromagnetic barrier operating in the underdamped regime. The system is probed also under the action of an additional dc current, which acts as a counter force trying to stop the ratchet. Under these conditions the ratchet works against the counter force, thus producing a non-zero output power. Finally, we estimate the efficiency of the $\varphi$ Josephson junction ratchet.

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R. Menditto, H. Sickinger, M. Weides, H. Kohlstedt, D. Koelle, R. Kleiner, E. Goldobin. 2016-07-26. Tunable $\varphi$ Josephson Junction ratchet. https://doi.org/10.1103/physreve.94.042202

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