Nonlinear conductivity inbis-tetramethyltetraselenafulvalene hexafluorophosphate [(TMTSF)2PF6]

At temperatures below the metal-to-semiconductor transition, and a little above, the conductivity of bis-tetramethyltetraselenafulvalene hexafluorophosphate [${\mathrm{}\left(\mathrm{TMTSF}\right)\mathrm{}}_2$P${\mathrm{F}}_6$] has been found to increase substantially with electric field intensity starting at fields as low as a few mV/cm. We show that the onset of this increase can be attributed to increase of mobility due to heating of the carriers by the field.