Tunable φ Josephson junction ratchet.

Menditto, R; Sickinger, H; Weides, M; Kohlstedt, H; Koelle, D; Kleiner, R; Goldobin, E · Phys Rev E · 2016

basic_science · Level V

Where this comes from

Abstract

We demonstrate experimentally the operation of a deterministic Josephson ratchet with tunable asymmetry. The ratchet is based on a φ 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 counterforce trying to stop the ratchet. Under these conditions the ratchet works against the counterforce, thus producing a nonzero output power. Finally, we estimate the efficiency of the φ Josephson junction ratchet.