Excitation of plasma oscillations by moving Josephson vortices in layered superconductors

Abstract

In the frame of an exactly solvable model we calculate electric and magnetic fields created by uniformly moving lattice of Josephson vortices driven by the transport current in the magnetic field parallel to conducting layers. The distribution of fields and currents is strongly modified at large velocities of the vortex lattice, plasma oscillations of superconducting electrons being excited by flux flow at low temperatures. This modifies the flux flow resistivity and results in interference features in I-V curves, thus regions of negative differential conductivity appear in which the uniform motion of the vortex lattice is not stable. The spectrum of electromagnetic radiation by moving vortices contains large peaks related to the excitation of plasma oscillations and to the Cherenkov radiation.