Strong coupling induced ultrasensitive chiral detection by metal-dielectric hybrid metasurface

Circular dichroism (CD) spectroscopy struggles to detect weak signals from small, chiral molecules due to limitations in light absorption. This study introduces a method for significantly enhancing CD signals using a metal-dielectric hybrid metasurface. The metasurface creates a superchiral hotspot that amplifies the chirality of nearby molecules. Two techniques are proposed to overcome signal cancellation between the intrinsic and induced signals to achieve an overall enhancement of the CD signal by up to 23,630 times. This approach has the potential for ultrasensitive detection of chiral molecules at the nanoscale, with applications in pharmacology, toxicology, and life sciences.