Anomalous effect of biased oscillating field on the switching behaviour: Modulating friction of charge carriers in nanowiresA. Rahman and M. K. Sanyal
Surface Physics Division, Saha Institute of Nuclear Physics - 1/AF, Bidhannagar, Kolkata 700064, India
received 18 July 2009; accepted in final form 3 November 2009; published November 2009
published online 3 December 2009
Ultra-low doped polypyrrole nanowires show characteristics of charge density waves (CDW) due to possible Wigner crystallization. The motion of CDW in these structurally discordered wires is expected to be different as CDW is not forming here due to underlying lattice. The results presented here show that the dc switching threshold voltage decreases rapidly with increasing ac bias, but the threshold current remains same. The ac component acts as an effective dc bias having value proportional to (ac amplitude)1.5. Near the switching transition, the voltage fluctuates and shows repetitive downward spikes. The results show several similarities with the “stick-slip” motion and aging-rejuvenation competition observed in jamming near the sliding motion in mechanical friction. The results also suggest an increase of dynamic correlation length in the presence of ac bias.
71.45.Lr - Charge-density-wave systems.
73.20.Qt - Electron solids.
73.63.-b - Electronic transport in nanoscale materials and structures.
© EPLA 2009