Hysteretic Depinning of Anisotropic CDW

We investigate the depinning transition in a dirty periodic medium considering a model of layered charge density waves as a prototype system. We find that depinning from strong disorder occurs via a two stage process, where, first, the pinned system experiences a continuous transition into a plastically sliding state and undergoes a second sharp hysteretic transition into a coherently moving 3D state at higher drives. In the weakly disordered system the depinning into a coherently sliding state remains continuous.