Power Coupling Optimization in 2D Waveguides by Evolutionary Algorithms

Inverse Design of Tapers by Bio-Inspired Algorithms

“…I. INTRODUCTION The taper waveguide coupler is a passive device composed by a photonic waveguide whose shape or transversal cross section varying along the direction of propagation [1]. Waveguide couplers are generally used to improve or enhance the light coupling efficiency between two waveguides with different transversal sections propagation characteristics.…”

“…For tapers with long length, the light can be coupled with negligible power loss into the output waveguide [2]- [4]. A drastic reduction of the taper's size will increase the power loss [1], [3].…”

“…The aim of this work is to extend the analysis presented in [1], where the number of segments and the segment width were considered constant and the size of taper region was fixed to 4.5 µm, which is smallest than other previously published. Here, the number of segments in the taper region will be swept from 10 to 15 making the structures of this work ranging from 3.0 to 4.5 µm being smaller than those found in [1]. Another contribution of this work is the analysis of the coupling efficiency varying the segments width in the values of 270 nm, 300 nm and 330 nm.…”

“…For the numerical modeling of these tapers, the FEM-2D formulation [9]- [12], is used to compute the field distribution and hence the coupled power can be obtained. On the other hand, the genetic algorithm (GA) and the artificial immune system (AIS) were used for the optimization of several photonic devices such as photonic crystals [11], [12], tapers in conventional waveguides [13], [14], and segmented tapers [1].…”

“…Some advantages of the models obtained with AIS and GA are the reduced time and computational effort, its simplicity and also its use in design and synthesis problems [1]. The GA and AIS parameters such as: Individual numbers, number of generations, mutation rates, and affinity have been adopted to be the optimized ones obtained in [1].…”