Whispering-Gallery Mode Enhanced SERS Sensing

Over the last decades, dielectric Whispering-Gallery Mode (WGM) micro-resonators, such as spherical or toroidal structures, have demonstrated their effectiveness for highly sensitive biochemical sensing [1]. When a WGM resonance is excited, light is tightly concentrated within a small modal volume, greatly enhancing the interaction with analytes. Conversely, Surface-Enhanced Raman Spectroscopy (SERS) is a powerful technique that merges the molecular fingerprinting capabilities of Raman spectroscopy with the optical near-field enhancement provided by localized surface-plasmon resonances (LSPRs) on metallic nanostructures. This combination enables the highly sensitive and selective detection of various substances, even in liquid environments [2].