Properties of strained Ta[S.sub.3] samples in the state of charge density wave and in the normal state

The uniaxial strain of quasi-one-dimensional conductor whiskers of orthorhombic Ta[S.sub.3] at a strain higher than [[epsilon].sub.c] ~ 0.8% leads to a sharp increase in the coherence of the properties of a charge density wave (CDW), which manifests itself in its motion in fields higher than threshold field [E.sub.t]. During uniaxial elongation, Ta[S.sub.3] is shown to exhibit the following unusual properties even in weak fields: Peierls transition temperature [T.sub.P] depends nonmonotonically on [epsilon], one-dimensional fluctuations weaken near [T.sub.p], and the coherence length of a charge density increases at T < [T.sub.P]. Investigations in fields higher than [E.sub.t] show that the ultracoherent properties of CDW exist in a wide temperature range and are retained when temperature increases up to [T.sub.P]. These properties of CDW make it possible to observe a sharp increase in [E.sub.t] near [T.sub.P] and an almost jumplike increase in [E.sub.t] at T < 90 K. The increase in [E.sub.t] at [T.sub.P] is explained by a decrease in the coherence volume of CDW because of a fluctuational suppression of the Peierls gap.