Single-layered all-dielectric chiral metasurfaces via Mie resonances

This study reports the design and optimization of a single-layer, all-dielectric chiral metasurface based on Mie resonances. The metasurface comprises dielectric cylinders with varying radii and exhibits strong performance in the near-infrared region, showing pronounced circular dichroism and optical activity. Its performance is analyzed using exact Mie resonance decomposition to calculate the scattering cross section and the phase of the electric dipole mode. The metasurface achieves a transmittance difference of 0.644 between right- and left-circularly polarized light at 1520 nm and a maximum optical activity of 150 \ifmmode^\circ\else\textdegree\fi{}/\ensuremath{\lambda}, despite a thickness of only 580 nm (about one-third of the target wavelength). These results demonstrate that a single-layer metasurface can deliver optical performance comparable to more complex chiral structures, highlighting its efficiency and potential for practical optical applications. Moreover, the design strategy can be extended to other chiral metasurfaces by varying the arrangement and spacing of the dielectric cylinders, offering advantages in fabrication simplicity and cost effectiveness. This work advances the development of next-generation chiral devices for sensing, polarization control, and nonlinear optical applications.