Negative differential resistance in uniaxially strained o-TaS3

A negative differential resistance has been observed in thin (cross section < 1 μm2) samples of o-TaS3 subjected to uniaxial stretch deformation in a temperature range 78–90K. fferential resistance changes its sign to a negative at fields Et1 several times higher, than a threshold field Et, and turns again to a positive one at the field Et2 (Et2 being up to 1.2 of Et1). The slope of I–V characteristics at E>Et2 is essentially higher, than that at E<Et1. ansition to a state with negative differential resistance is accompanied by intermittent-like conductivity oscillations. The main features observed are quite good reproducible during many cycles of deformation, field application and thermal cycling. served phenomena are discussed within a model providing a transfer from a normal carrier screening current dissipative mechanism, dominating at low temperatures and fields to the phonon/phason ones at high temperatures and high fields.