Performance analysis of a floating multi-focus metalens in LWPT: influence of aperture and thickness

Laser wireless power transfer (LWPT) offers a viable approach to overcoming the endurance limitations of unmanned aerial vehicles (UAVs) by enabling continuous, long-range power delivery. However, beam divergence, misalignment, and non-uniform illumination at photovoltaic (PV) receivers hinder its practical implementation. Here, we present a lightweight, floating multi-focus metalens that directly concentrates the laser beam near the PV receiver, improving both energy delivery efficiency and spatial uniformity. Numerical simulations demonstrate that increasing the metalens aperture significantly enhances energy concentration while maintaining over 98% beam uniformity. The focusing efficiency is also strongly influenced by nanopillar height, with deviations from the optimal value reducing the polarization conversion efficiency of the metalens. These results provide design guidelines for high-performance, flexible optical components and pave the way for stable, efficient LWPT in dynamic aerial environments.