Dynamics of sliding charge-density waves in 4-ε dimensions

The critical behavior of sliding charge-density waves just above threshold is analyzed. In 4-ε dimensions, the exponent ζ, defined through ${\mathit{I}}_{\mathrm{CDW}}$∼(V-${\mathit{V}}_{\mathit{T}}$ ${)}^{\mathrm{\zeta }}$, is found to be 1-ε/6+O(${\mathrm{\epsilon }}^2$). Two different correlation lengths are found, with exponents ν=1/2 exactly and ${\nu }_{\mathrm{FS}}$=2/d+O(${\mathrm{\epsilon }}^2$). These results compare favorable with recent numerical results in two and three dimensions.