Bi-directional propagation leaky modes in a periodic chain of dielectric circular rods.

In this paper, a periodic chain composed of two-dimensional dielectric cylindrical inclusions was studied based on the Fourier series expansion method with perfectly matched layers. Phase and attenuation constants associated with guided modes, forward propagation leaky modes, and backward propagation leaky modes, were conceptually proposed and numerically examined. In particular, the relationships between the backward propagation mode, leaky mode, and propagation constant were explained in the second-order Bragg reflection region. This simple structure was investigated with the goal of realizing an efficient guiding device. Phase and attenuation constant results were compared with the results obtained using the Lattice Sums technique with the T-matrix approach and FDTD method; very good agreement was observed between these methods. (c) 2018 Optical Society of America under the terms of the OSA Open Access Publishing Agreement