Genetically optimized All-dielectric metasurfaces

TL;DR

This paper introduces a genetic algorithm-based design method for all-dielectric metasurfaces, achieving high efficiency and wide-angle beam deflection in visible and infrared spectra.

Contribution

It presents a novel genetic optimization approach that significantly improves transmission efficiency of dielectric metasurfaces for wide-angle applications.

Findings

Achieved up to 87.2% transmission efficiency at 580nm

Realized wide-angle deflection of 65° in visible spectrum

Enhanced efficiency without complex structural arrangements

Abstract

We present and study theoretically a new design approach for obtaining wide angle, highly efficient, all-dielectric metasurfaces. As a concrete example we focus on optimizing flat beam deflector for both the infra-red and visible spectral regions. Transmission efficiencies of up to 87.2% are obtained theoretically for deflection angle of 65{\deg} in visible (580nm) spectrum and up to 82% for deflection angle of 30.5{\deg} at telecom wavelength (1550nm). The enhanced efficiencies at wide deflection angles are obtained by genetic optimization of the nano-structures comprising the metasurface. Compared to previously employed design approaches, our approach enhances the transmission efficiency substantially without sacrificing rectangular grid arrangement and facilitates the realization of wide angle flat deflectors and holograms/lenses.