Inverse-designed superchiral dielectric metasurfaces

Chirality, essential for distinguishing molecular enantiomers, impacts various scientific fields. Circular dichroism (CD) spectroscopy, which measures differential absorption of circularly polarized light, is limited by weak chiral-optical interactions, yielding minimal signals. Superchiral metasurfaces, enhancing optical chirality, offer improved CD signal and interaction with chiral molecules, necessitating advanced development for accurate analysis. This study presents a novel two-stage design methodology for optimizing superchiral metasurfaces, employing a neural network-based optimizer and adjoint topology optimization for enhanced optical chirality density. The results provide a platform for sensitive CD spectroscopy, facilitating fast optimization of metasurface unit cells for better chiral molecule analysis.