Fluxon diode using semicircular Josephson junction

We propose and study a novel way to construct relativistic fluxon based diodes using semicircular Josephson junctions. Theoretical studies show that an external static magnetic field applied parallel to the dielectric barrier of a semicircular Josephson junction has opposite polarities at the ends of the junction and because of that opposite polarity fluxons can enter the junction from the ends under a properly biased dc current. However, if the direction of the current is reversed, flux penetration and propagation is not possible and flux-free state exists in the junction. This unique phenomenon cannot be achieved in any other Josephson junction geometry and the junction behaves as a perfect diode. (C) 2002 Published by Elsevier Science B.V.