Robust Design of Autofocused Airy Beam-Based Multifocal Metalens With Tunable Intensities

Abstract

Optical metasurfaces with versatile focal properties have great importance and adaptability in photonic systems and potential applications. The unique capability of the ultra-compact device in forming and modulating light fields is triggered to configure multifocal setups. This study introduces a geometric metasurface consisting of dielectric cross-shaped metaatoms with a suitable phase profile operating in the visible regime that can transport the conjugate focal spot of the auto-focused Airy beam (AFAB) into real space by adding the proper convex lens profile and resulting in three foci whose positions and intensities can be adjusted without redesigning metaatoms architecture. The cross-shaped meta-atoms with complete control of the amplitude and phase of the incident light have considered diverse functionalities for the x-and y-components of the incident light, generating six focal spots with high adjustable intensities shown in free space. The proposed hybrid metalens has shown robustness against change in geometrical design while controlling multifocal setups, which can be useful in developing polarization-sensitive devices, photonics, medicine, micromachining and imaging applications to realize beneficial results.

Keywords

• Dielectric metasurfaces
• Airy beams
• metalens
• diffraction
• propagation