Low-frequency noise and memory effect in the charge-density-wave transport ofRb0.30MoO3

Low-frequency noise (~1 Hz) is found in the nonlinear transport regime due to the depinning of the charge-density wave in the blue bronze ${\mathrm{Rb}}_{0.30}$ ${\mathrm{MoO}}_3$ below the Peierls transition. These low frequencies are linear with the excess charge-density-wave current. The corresponding phenomena depend on the cooling process. Erratic voltage fluctuations follow a quenching without an applied dc current. Coherent pulses or oscillations depending on the cooling rate are found after a cooling with an applied dc current. We propose that these phenomena are related to the motion of charge-density-wave domains coupled to mobile defects.