Metastability, memory, and dynamics of charge density waves.

Charge density waves pinned by disorder have many possible metastable configurations. The existence of metastable states give rise to generic glasslike behavior including hysteresis and power law time decays of the polarizations. The characteristic behavior is controlled by high-energy metastable states which are marginally stable to perturbations. One consequence is a dynamic memory effect, whereby the system can be trained to remember the length of a voltage pulse.