We investigate the conductivity variation with density of compacted vapour-grown carbon fibre (VGCF). The results indicate a typical transition between a non-linear domain at low compaction conditions and a regime where the conductivity increases roughly linearly with density when the sample is...

We derive the first dynamic correction to the effective refractive index for a square array of cylinders (of finite or infinite refractive index), subject to a low-frequency incident radiation. This correction also imposes constraints on the wave number region for which the Lorentz-Lorenz...

Fractal nanostructured materials, such as nanocomposites and self-affine thin films, are shown to possess giant optical nonlinearities. The enhancement results from the sub-wavelength localization of dipolar modes and strong local field fluctuations.