Observation of the Correlated Vortex Flow inNbSe2with Magnetic Decoration

In weakly pinning type-II superconductors the vortex lattice can flow coherently under the action of a Lorentz force. This type of collective vortex motion in a random potential is manifested by channeling of the vortex flow along preferred paths which are stable in time. We present direct experimental observations of such vortex flow “channels” obtained with magnetic decoration experiments on ${\mathrm{NbSe}}_2$ single crystals.