Impurities potential effect on the charge density wave dynamics in one-dimensional systems

In this work, we present in the weak pinning case the numerical simulation results of the one-dimensional deformable charge density wave (CDW) properties considering the potential amplitude fluctuations effect generated by different impurity types randomly distributed in the lattice. When the electric field approaches threshold value ET, the static equilibrium characteristic time τ and the polarization PCDW become large and seem to diverge at critical field Ecr from below ET following a power law 1−(E/Ecr)]^−α where α is an impurity dependant critical exponent. This divergence indicates that the CDW depinning can be described in terms of a dynamical critical phenomena, where the critical field Ecr plays the role of a transition temperature as in ordinary phase transitions. In agreement with several experimental results, we show that the electric current density JCDW and electric conductivity σCDW follow respectively a power law β(E/ET)−1] and (ET/E)ν(E/ET)−1] where β and ν are critical exponents. This results are analogous to these obtained in the case of one impurity type.