Design of single-mode polarization splitter with a configuration of asymmetric Y-junction in two-dimensional honeycomb photonic crystal

摘要

Single-mode polarization splitter with a configuration of asymmetric Y-junction is proposed in two-dimensional (2D) honeycomb photonic crystal (PhC) of dielectric rods. Six dielectric rods with a radius of 0.12α (The radius of a regular rod is 0.25α.) are placed on the junction region to block transverse magnetic ? light and to pass transverse electric (TE) light by the bandgap effect, where α is the shortest distance between two regular rods. And one rod with a radius of 0.32α is employed to enhance the bending efficiency of TM light through a resonance effect. Device performance is simulated by the finite-difference time-domain method. At 1550 nm wavelength, polarization extinction ratio (PER) between the two output waveguides is larger than 20 dB for either TE or TM input. Polarization splitting as a function of wavelength is also studied in this paper.