Non-linear conductivity of monoclinic TaS3

Strongly non-ohmic conduction is observed in the semiconducting charge-density-wave (CDW) state of monoclinic TaS₃ above a very sharp threshold field. These features could be interpreted in terms of depinning or tunneling of pinned CDW under applied electric field. We also found that large noise appears with the onset of the non-linear conductivity and fades away as the current through the samples is increased, which behaves as the decreasing function of frequency.