Irreversibility and nonequilibrium dynamics in the pinned charge-density wave

In the pinned state the charge-density wave displays irreversibility and nonequilibrium dynamics of an unusual nature as the applied voltage V is cycled. Relaxation from unstable states terminate at end points. In the process of depinning, the charge-density wave traverses a wide spectrum of time scales. The close relation of the time scales to the pulse-memory effect and ac dielectric constant is discussed.