Title :
Optimization of Construction of Multiple One-Dimensional Photonic Crystals to Extend Bandgap by Genetic Algorithm
Author_Institution :
Coll. of Opt. & Electron. Technol., China Jiliang Univ., Hangzhou, China
fDate :
4/1/2010 12:00:00 AM
Abstract :
A method is presented to design a layer structure, consisting of a few different one-dimensional photonic crystals merged together, having an extended band gap. Hereby, the thicknesses of the two layers of each unit cell, corresponding to the involved photonic crystals, are optimized using a genetic algorithm. As numerical examples, two structures are constructed by this method, one structure is composed of four one-dimensional photonic crystals by using TiO2 and SiO2, the other is composed of two one-dimensional photonic crystals based on two materials with the refractive index of 4.6 and 1.6. Their theoretical omnidirectional relative bandwidths (defined as the gap to midgap ratio) are 51.36% and 91.72% respectively. The reflection spectra calculated by the transfer matrix method agree with the correspondent band gap.
Keywords :
genetic algorithms; infrared spectra; optical design techniques; optical multilayers; photonic band gap; photonic crystals; reflectivity; refractive index; silicon compounds; titanium compounds; visible spectra; SiO2; Te; TiO2; genetic algorithm; multiple 1D photonic crystal hybrid structure; omnidirectional band gap; omnidirectional relative bandwidth; optical design; optimization; reflection spectra; refractive index; transfer matrix method; Band gap extension genetic algorithm; coatings; one-dimensional photonic crystal;
Journal_Title :
Lightwave Technology, Journal of
DOI :
10.1109/JLT.2009.2039194
