Non-linear conductivity of NbS3 in pressure induced metal state

Temperature and voltage dependencies of conduction of a quasi-one-dimensional conductor NbS3 after its transition into a metallic state has been studied at pressures higher than 6 GPa. The differential resistance R = dV /dI measured at small biases (the electric field E below 2 V/cm) demonstrate a considerable growth upon cooling below 20 K accompanied by appearance of the non-linear conduction. Both the growth and nonlinear conduction disappear at E > 3 V/cm or when the temperature exceeds 40 K. A narrow dip visible only at much smaller fields E < 20 mV/cm is superimposed over that nonlinear background when cooling below 3.7 K. (© 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)