Impurity pinning of charge-density waves and spin-density waves

Abstract

We reexamine the threshold electric field of the charge-density wave (CDW) within the Fukuyama-Lee-Rice model, where the temperature dependence of the effective Hamiltonian for the phase \ensuremath{\varphi} of the CDW is explicitly included. Our theory describes very well the temperature dependence of the threshold field in ${\mathrm{NbSe}}_{3}$ when the effects of the thermal fluctations of \ensuremath{\varphi} are included. An extension of the model for the spin-density wave predicts that the threshold electric field in the spin-density wave does not exhibit a divergence at T=${T}_{c}$ but is almost constant for T\ensuremath{\le}0.5${T}_{c}$ and slightly increases (\ensuremath{\sim}33%) near T=${T}_{c}$.