Clogging transition for vortices driven by dc current

The clogging phenomenon is ubiquitously observed in various systems. It was predicted numerically that a change from the flow state to the completely clogged state is a nonequilibrium phase transition. However, to the best of our knowledge, there is no experimental study demonstrating this prediction. Here, we study the critical dynamics of superconducting vortices near the clogging transition, as well as near the depinning transition, driven by dc current. The relaxation times to reach the stationary flow or completely clogged state plotted against the current show a power law divergence on both sides of the critical current, which coincides with the depinning current, indicating the existence of the nonequilibrium clogging transition. The critical exponents of both transitions are in agreement with the values expected for a nonequilibrium absorbing phase transition in the two-dimensional directed-percolation universality class. This work will lead to a potential application, such as, prediction and control of clogging, which are crucial in various scientific and engineering fields.