Accelerated near-field data acquisition for designing large metalenses using circular symmetry

Due to limitations in computational resources, researchers often bypass the validation of simulation results when investigating large metalenses, especially those significantly larger than the operational wavelength. Typically, they might directly employ simulate-derived units or perform preliminary validation using smaller-scale metalenses before advancing to full-scale experiments. To address this challenge, we propose a method to accelerate the near-field data acquisition phase, which is often the most time-consuming. This involves constructing two-dimensional near-field data by symmetrically expanding a one-dimensional metalens in a circular pattern. Our findings show that this approach can achieve a speedup of over 100 times, with potential for even greater efficiency as metalens size increases. Additionally, this technique is applicable to the computation of multi-level diffraction lenses. In the future, our method is expected to provide researchers with more accurate data for guiding experimental designs, thereby increasing the likelihood of success.