An Interesting Optical Behavior of Bent/Multi-branch Waveguides Based on Hexagonal-lattice Photonic Crystals

For the hexagonal-lattice photonic crystal waveguides with the 60/120-bent sections, the light waves prefer to turn into the 120-bent section rather than propagate along the 60-bent ones. Our FDTD simulation results show that the backward optical fields (propagating along the 120-bent section) are more intense than the forward ones (propagating along the 60-bent section). And these results are in good agreement with those simulated by RSoft-BeamPROP.