Classical Phase Fluctuations in Incommensurate Peierls Chains
  In the pseudogap regime of one-dimensional incommensurate Peierls systems, fluctuations of the phase of the order parameter prohibit the emergence of long-range order and generate a finite correlation length. For classical phase fluctuations, we present exact results for the average electronic density of states, the mean localization length, the electronic specific heat and the spin susceptibility at low temperatures. Our results for the susceptibility give a good fit to experimental data. 
Lorenz Bartosch and Peter Kopietz