### Résumé

We use a genetic algorithm to optimize broadband absorption by 2-D periodic arrays of pyramidal structures

made of one, two or three stacks of nickel/poly(methyl methacrylate) (Ni/PMMA) layers. The objective was

to achieve perfect absorption of normally incident radiations with wavelengths comprised between 420 and 1600

nm. The absorption spectrum of these pyramidal structures is calculated by a Rigorous Coupled Waves Analysis

method. A genetic algorithm is then used to determine optimal values for the period of the system, the lateral

dimensions of each stack of Ni/PMMA and the width of each layer of PMMA. The idea consists in working

with a population of individuals that represent possible solutions to the problem. The best individuals are

selected. They generate new individuals for the next generation. Random mutations in the coding of parameters

are introduced. A local optimization procedure that works on the data collected by the algorithm is used to

accelerate convergence. This strategy is repeated from generation to generation in order to determine a globally

optimal set of parameters. The optimal three-stacks structure determined by this approach turns out to absorb

99.8% of the incident radiations over the considered 420-1600 nm wavelength range. A value of 99.4% is achieved

with pyramids made of only two stacks of Ni/PMMA layers while a one-stack pyramidal structure absorbs 95.0%

over the same wavelength range. These results are surprisingly competitive considering the small number of layers

involved in the design. They prove the interest of an evolutionary approach to optical engineering problems.

made of one, two or three stacks of nickel/poly(methyl methacrylate) (Ni/PMMA) layers. The objective was

to achieve perfect absorption of normally incident radiations with wavelengths comprised between 420 and 1600

nm. The absorption spectrum of these pyramidal structures is calculated by a Rigorous Coupled Waves Analysis

method. A genetic algorithm is then used to determine optimal values for the period of the system, the lateral

dimensions of each stack of Ni/PMMA and the width of each layer of PMMA. The idea consists in working

with a population of individuals that represent possible solutions to the problem. The best individuals are

selected. They generate new individuals for the next generation. Random mutations in the coding of parameters

are introduced. A local optimization procedure that works on the data collected by the algorithm is used to

accelerate convergence. This strategy is repeated from generation to generation in order to determine a globally

optimal set of parameters. The optimal three-stacks structure determined by this approach turns out to absorb

99.8% of the incident radiations over the considered 420-1600 nm wavelength range. A value of 99.4% is achieved

with pyramids made of only two stacks of Ni/PMMA layers while a one-stack pyramidal structure absorbs 95.0%

over the same wavelength range. These results are surprisingly competitive considering the small number of layers

involved in the design. They prove the interest of an evolutionary approach to optical engineering problems.

langue originale | Anglais |
---|---|

titre | Proceedings of SPIE |

rédacteurs en chef | Anatoly V. Zayats, Allan D. Boardman, Kevin F. MacDonald |

Pages | 1067127-1 |

Nombre de pages | 11 |

Volume | 10671 |

ISBN (Electronique) | 9781510618688 |

Les DOIs | |

Etat de la publication | Publié - 2018 |

Evénement | SPIE Photonics Europe - Strasbourg Convention & Exhibition Centre, Strasbourg, France Durée: 22 avr. 2018 → 26 avr. 2018 https://spie.org/conferences-and-exhibitions/photonics-europe |

### Une conférence

Une conférence | SPIE Photonics Europe |
---|---|

Pays | France |

La ville | Strasbourg |

période | 22/04/18 → 26/04/18 |

Adresse Internet |

### Empreinte digitale

### Contient cette citation

Mayer, A., & Lobet, M. (2018). UV to near-infrared broadband pyramidal absorbers via a genetic algorithm optimization approach. Dans A. V. Zayats, A. D. Boardman, & K. F. MacDonald (eds.),

*Proceedings of SPIE*(Vol 10671, p. 1067127-1). [1067127] https://doi.org/10.1117/12.2303823