PHOTONIC CRYSTALS & METAMATERIAL FILTERS BASED ON 2D ARRAYS OF SILICON NANOPILLARS

Highly dense two-dimensional periodic arrays of nano-scaled silicon pillars present interesting photonic band gaps and the capacity to act as photonic crystals which can mould, manipulate and guide light. We demonstrate finite element modelling of silicon pillars based photonic crystals and their effective use in applications like waveguides, optical power dividers, multiplexers and switches. The optical wave propagation through these structures was thoroughly simulated and analysed, confirming their high efficiency. The band gaps studied through the plane wave expansion method are also presented. Later the fabrication of highly periodic two-dimensional arrays of silicon pillars through the process of etching is also explained. The arrays with pillar radius of 50 nm and lattice constant of 400 nm were successfully utilised as photonic crystal waveguides and their measured results are reported. Moreover, the silicon nanopillars sputtered with noble metals can also display artificial optical properties and act as metamaterials due to the mutual plasmonic coupling effects. We report the theoretical results for the silicon nanopillars based metamaterial high-pass filter.