High-efficiency Bessel beam array generation by Huygens metasurfaces

Bessel beams have attracted considerable interest because of their unique non-diffractive, self-healing characteristics. Different approaches have been proposed to generate Bessel beams, such as using axicons, diffractive optical elements, composite holograms, or spatial light modulators. However, these approaches have suffered from limited numerical aperture, low efficiency, polarization-dependent properties, etc. Here, by utilizing dielectric Huygens metasurfaces as ultrathin, compact platforms by integrating the functionalities of Dammann gratings and axicons, we successfully demonstrate multiple Bessel beam generation with polarization-independent property. The number of two-dimensional arrays can be controlled flexibly, which can enhance information capacity with a total efficiency that can reach 66.36%. This method can have various applications, such as parallel laser fabrication, efficient optical tweezers, and optical communication.