The Design of a 2×1 Beam Combiner in Two-Dimension Photonic Crystal

A novel 2×1 beam combiner in two-dimension photonic crystal (PC) is presented. The rate-matching condition is analyzed based on coupled-mode theory. The transmittance performance of T-shaped branch in square lattice is simulated by the finite-difference time-domain (FDTD) method. By altering the radius of dielectric rods at vertex, we match the amplitude decay rates of three waveguides. Numerical simulation results show the PC combiner has a perfect transmittance when the rate-matching condition is satisfied.