Gliding dislocations in a driven vortex lattice

The dynamics of dislocations in a two-dimensional vortex lattice is studied in the presence of a pinning potential and a transport current. In a vortex lattice drifting with velocity $v$ a glide velocity $V_d$ of the dislocation with respect to the vortex lattice is found to decay like $V_d \sim v^{-4}$ for large drive. From this result the velocity for the crossover between a regime of coherent elastic motion and a regime of incoherent plastic motion of vortices is estimated.