Abstract

We propose a single layer metasurface for achromatic focusing of two different wavelengths with two different spatial structures for high-resolution STED microscopy, which is difficult to achieve in the conventional method. By employing the dichroic birefringent metaatom technique, the metasurface is specifically designed to focus excitation Gaussian beam of 532nm and doughnut-shaped depletion spot with a vortex phase of 660nm at the same focal distance. The proposed approach could enable high resolution, ultracompact STED microscope.

© 2023 The Author(s)