Chiral Metasurface Multifocal Lens in the Terahertz Band Based on Deep Learning

Abstract

Chiral metasurfaces have garnered significant interest as an emerging field of metamaterials, primarily due to their exceptional capability to manipulate phase distributions at interfaces. However, the on-demand design of chiral metasurface structures remains a challenging task. To address this challenge, this paper introduces a deep learning-based network model for rapid calculation of chiral metasurface structure parameters. The network achieves a mean absolute error (MAE) of 0.025 and enables the design of chiral metasurface structures with a circular dichroism (CD) of 0.41 at a frequency of 1.169 THz. By changing the phase of the chiral metasurface, it is possible to produce not only a monofocal lens but also a multifocal lens. Well-designed chiral metasurface lenses allow us to control the number and position of focal points of the light field. This chiral metasurface, designed using deep learning, demonstrates great multifocal focus characteristics and holds great potential for a wide range of applications in sensing and holography.

AI-Based Metamaterial Design

“…Other examples of recent DNN-based applications in optic metalenses have encompassed a diverse range and include the development of chiral metasurface multifocal lens in the Terahertz band and miniaturized wide-angle fisheye lens among other applications. , Wang et al have designed bifocal metalens that can independently focus and its bidirectional circular polarized light. In the traditional sense, simulations for meta-lens design have a high computational cost thus, the group suggested a DL-forward genetic algorithm to design the metalens parameters efficiently.…”

“…Other examples of recent DNN-based applications in optic metalenses have encompassed a diverse range and include the development of chiral metasurface multifocal lens in the Terahertz band 140 and miniaturized wide-angle fisheye lens 141 among other applications. 142 , 143 Wang et al have designed bifocal metalens that can independently focus and its bidirectional circular polarized light.…”