Structure and orientation of the moving vortex lattice in clean type-II superconductors

The dynamics of the moving vortex lattice is considered in the framework of the time-dependent Ginzburg-Landau equation neglecting the effects of pinning. At high flux velocities the pinning dominated dynamics is expected to crossover into the interactions dominated dynamics for very clean materials recently studied experimentally. The stationary lattice structure and orientation depend on the flux flow velocity. For relatively velocities V<V _c = √8πB/Φ ₀ /γ, where γ is the inverse diffusion constant in the time-dependent Ginzburg-Landau equation, and the vortex lattice has a different orientation than for V> V _c . The two orientations can be desribed as motion "in channels" and motion of "lines of vortices perpendicular to the direction of motion." Although we start from the lowest Landau level approximation, corrections to conductivity and the vortex lattice energy dissipation from higher Landau levels are systematically calculated and compared to a recent experiment.