Voltage Induced Anomalous Conductance Switching Behaviour in Nematic Liquid Crystal-Multiwalled Carbon Nanotube Composite

摘要

Investigations on the voltage induced conductance switching behavior in the nematic liquid crystalmultiwalled carbon nanotube composite have performed. We have found that, the system formed electrical conduction pathways with increasing voltages. Anomalous conductance switching took place at a certain threshold voltage. Percolation threshold voltage depends on the frequencies of the measuring electric field. We have made an analogy between concentration dependent percolation and voltage induced percolation. A two dimensional (2D) renormalization model calculation reveals that if the CNTs form a 2D network then percolation threshold concentration (p_c) should be 0.768. After careful analysis we have found that voltage analogy of percolation threshold concentration in our system is also very close to the above value. The connectivity exponent (β) for 2D site percolation agrees well with our proposed voltage induced percolation connectivity exponent. Which gives a glimpse that voltage induced percolating network may forms a two dimensional network in this particular system.