title: Tunable φ Josephson junction ratchet.
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.
authors.affiliation: Physikalisches Institut and Center for Quantum Science in LISA+, Universität Tübingen, Auf der Morgenstelle 14, D-72076 Tübingen, Germany.
authors.forename: R
authors.initials: R
authors.lastname: Menditto
authors.affiliation: Physikalisches Institut and Center for Quantum Science in LISA+, Universität Tübingen, Auf der Morgenstelle 14, D-72076 Tübingen, Germany.
authors.forename: H
authors.initials: H
authors.lastname: Sickinger
authors.affiliation: Physikalisches Institut, Karlsruher Institut für Technologie, D-76128 Karlsruhe, Germany.
authors.forename: M
authors.initials: M
authors.lastname: Weides
authors.affiliation: Nanoelektronik, Technische Fakultät, Christian-Albrechts-Universität zu Kiel, D-24143 Kiel, Germany.
authors.forename: H
authors.initials: H
authors.lastname: Kohlstedt
authors.affiliation: Physikalisches Institut and Center for Quantum Science in LISA+, Universität Tübingen, Auf der Morgenstelle 14, D-72076 Tübingen, Germany.
authors.forename: D
authors.initials: D
authors.lastname: Koelle
authors.affiliation: Physikalisches Institut and Center for Quantum Science in LISA+, Universität Tübingen, Auf der Morgenstelle 14, D-72076 Tübingen, Germany.
authors.forename: R
authors.initials: R
authors.lastname: Kleiner
authors.affiliation: Physikalisches Institut and Center for Quantum Science in LISA+, Universität Tübingen, Auf der Morgenstelle 14, D-72076 Tübingen, Germany.
authors.forename: E
authors.initials: E
authors.lastname: Goldobin