Structure factor of weakly pinned charge-density waves in sub-threshold electric field

Abstract

The electric field dependence of the static electronic structure factor S(x) of a one-dimensional charge-density wave (CDW) is investigated theoretically within the Fukuyama-Lee-Rice Hamiltonian in the limit of weak pinning and for sub-threshold electric fields. By a perturbation treatment of a Fokker-Planck equation with respect to the electric field it is found that the CDW splits into a closely spaced series of partial waves. The dominating phase correlation length is found to decrease slightly until the threshold electric field is reached. Partial Q-shifts in S(x) are also obtained and they are related to the capacitance of the CDW and the associated phenomenon of charging.