Polarization-multiplexed all-dielectric metasurfaces for anomalous transmission and airy beam generation

Silicon-based metasurfaces exhibit significant potential for manipulating optical wavefronts across the visible and infrared wavelength ranges due to their compact size and compatibility with CMOS technology. However, previous research has predominantly focused on developing either monofunctional devices or switchable bifunctional devices. In this work, we propose a silicon-based bifunctional metasurface that demonstrates polarization-selective anomalous transmission and Airy beam shaping within the visible spectrum. The metasurface is composed of an array of 80 × 201 rectangular dielectric silicon elements deposited on a silicon dioxide substrate. We thoroughly analyze the relationship between phase shift and geometric dimensions to enable the successful design of the target metasurface. By carefully selecting the periodicity and geometry of the unit cell, we achieve anomalous transmission and Airy beam shaping for two orthogonal linear polarization states of normally incident light at a wavelength of 632.8 nm. Additionally, we also demonstrate a polarization-multiplexed function for anomalous transmission and autofocusing Airy beam using a similar concept. Our approach presents a novel paradigm for designing multifunctional optical devices that operate in the visible spectrum.