Electrically Tunable Metalens Based on PEDOT:PSS

Tunable metalenses are planar optical elements that hold immense potential in the field of integrated optics, enabling reconfigurable focusing without the bulkiness associated with traditional lenses. This study proposes an electrically tunable metalens which integrates poly(3,4-ethylenedioxythiophene)-polystyrenesulfonate (PEDOT:PSS) with a metasurface. The focal length is electrically controlled through electrochemical modulation of the PEDOT:PSS film thickness and deintercalation in an electrolyte. The Fresnel zone plate (FZP) design is employed to simplify the phase profile and reduce optimization complexity. More importantly, the modulated PSO algorithm is implemented to inverse-design the units and suppress inter-unit phase crosstalk. Simulation results demonstrate that the metalens achieves diffraction-limited focusing, with a zoom ratio reaching 10:1. This work provides a feasible strategy for developing high-performance dynamically tunable metalens, with promising applications in miniaturized imaging, microscopy, and integrated photonic systems.