Transverse Bragg reflection filtering in a dielectric waveguide

We demonstrate that transverse Bragg stacks symmetrically placed about a dielectric waveguide can effectively filter a fundamental mode in the dielectric waveguide. A narrow bandpass dielectric waveguide filter based on transverse Bragg reflection is proposed and investigated numerically. The results calculated indicate that for the filter with Bragg stacks of longitudinal length 3.86 μm, there is high transmission (≥95%) in the wavelength range of 1294-1326 nm, whereas there is loss as high as 93.4% at 1550 nm. Owing to its simple and compact structure, this filter is expected to be applied to highly dense photonic integrated circuits.