Fabrication and optical characteristics of silicon-based twodimensional photonic crystal wavelength division multiplexing splitter

Photonic crystals have many potential applications because of their ability to control light-wave propagation. In this paper, we have investigated PC-based optical waveguides implemented into wavelength division multiplexing (WDM) systems. The WDM splitters based on a PC waveguide coupler with square lattice are proposed. Their wavelength multiplexing properties are numerically investigated by using the finite-difference time-domain method. Rod-type photonic crystal structures were fabricated in silicon by electron beam lithography and dry-etching techniques. The WDM splitters were fabricated from two-dimensional photonic crystal waveguides. Transmission spectra were calculated by using finite-difference time-domain method. The WDM splitters can be used in infrared region. Such an approach to photonic element systems should enable new applications for designing components in photonic integrated circuits.