Nonlinearity exponent in low dimensional nanotubes and nanowires

A scaling formalism is used to analyze non-Ohmic conductance-voltage data in nanowires of an isolated potassium manganese oxide K0.27MnO2·0.5H2O and a poly(3,4-ethylenedioxythiophene) (PEDOT) and nanotubes of conducting polypyrrole at different temperatures. This scaling analysis provides a single voltage scale for non-Ohmic conduction which scales with Ohmic conductance with an exponent xT, called nonlinearity exponent. A detailed analysis reveals that the onset exponents xT are different in different systems. Non-Ohmic conduction and the nonlinearity exponents in these low-dimensional nanostructures are analyzed within the framework of scaling approach and existing theoretical models.