Nonlinear Transport in Tetrathiafulvalene-Tetracyanoquinodimethane (TTF-TCNQ) at Low Temperatures

An experimental study of electrical transport phenomena in TTF-TCNQ in the low-temperature ($T<\mathrm{}4.2\mathrm{}$ K) dielectric regime is reported. The current-voltage curves are nonlinear with conductance increasing with increasing voltage. The observed nonlinearity is insensitive to radiation-induced defects at the fraction of a percent level. The data are discussed in terms of electric field depinning of the incommensurate charge-density wave with a critical electric field of approximately 1.5 × ${10}^2$ V/cm.