Relativistic flux quantum in a field-induced deterministic ratchet - art. no. 054515

We address the problem of a relativistic particle in a periodic asymmetric potential of the ratchet type. As a solid-state realization of such a parti cle, we consider a single-flux quantum in a long annular Josephson junction embedded in an inhomogeneous magnetic field. A deterministic (nonthermal) regime is theoretically investigated and compared with numerical results. T he ratchet velocity of the relativistic fluxon is found qualitatively diffe rent from that of a nonrelativistic particle.