We explore the dynamics of driven magnetic flux lines in disordered type-IIsuperconductors in the presence of twin boundaries oriented parallel to thedirection of the applied magnetic field, using a three-dimensional elastic linemodel simulated with Langevin molecular dynamics. The lines are drivenperpendicular to the planes to model the effect of an electric current appliedparallel to the planes and perpendicular to the magnetic field. A study of thelong-time non-equilibrium steady states for several sample thicknesses L anddrive strengths F_d reveals a rich collection of dynamical regimes spanning aremarkably broad depinning transition region that separates the pinned andmoving-lattice states of vortex matter. We perform novel direct measurements offlux line excitations such as half-loops and double kinks, and quantitativelyanalyze their excitation occurrence distributions to characterize thetopologically rich flux flow profile and generate a boundary curve separatingthe regions of linear and non-linear transport in the (L, F_d) plane. Richstatic and dynamic visualizations of the vortex matter in different driveregimes supplement the quantitative results obtained.
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