Analysis for '101' channels of MUX/DEMUX using grating SOI Structure at sub nanometer scale

In this paper, we present simulation studies to envisage “101'' channels of optical multiplexer and demultiplexer using silicon grating SOI structure. Here silicon grating structure is realized by the combination of 68 periodic layers of silicon monoxide and silicon, however, defects at the 18th and 52nd position are cogitated with the above structure, where the defect is realized by the substitution of air instead of silicon at the 18th and 52nd position. As far as numbers of channels are concerned, the wavelength range of 1500 nm-1600 nm is considered in this investigation. Here both absorption and reflection losses are included to compute the transmitted wavelength. The reason for choosing such structure is that absorption loss is found zero at same wavelength range. The simulation is carried out using the plane wave expansion method for obtaining reflectance from such structure. An intriguing result is seen on the subnanometer scale of the grating layer; for an example; each grating structure is allowed single wavelength only and completely forbid others. Aside this, simulation results revealed that an interesting linear variation (R2 = 0.999) of allowed wavelength with respect to grating length is observed. Present simulation work divulges that the long grating SOI structure permits higher wavelength, where lower wavelengths are allowed by short grating SOI structure.