Study on compact polarization beam splitters based on directional coupling in Bragg reflection waveguides

Directional coupling in dual-channel Bragg reflection waveguides are investigated through plane-wave expansion and finite difference time-domain methods. A polarization beam splitter based on directional coupling in Bragg reflection waveguides is proposed, and its transmission characteristics are investigated by using the finite different time-domain method. Calculated results indicate that, for the polarization beam splitter with the coupling length of 59.76 mu m, TM0 and TE0 modes at a wavelength of 1.55 mu m can be spatially separated, and the corresponding transmittances are 91.72% and 97.97%, respectively. The compact polarization beam splitter is expected to be applied to high density photonic integrated circuits. (C) 2015 Optical Society of America