Abstract
To unlock the future of ultra-sensitive molecular detection with the SERS substrate, understanding the interactions between plasmonic nanostructures and electromagnetic fields is crucial for advancing Surface-Enhanced Raman Spectroscopy (SERS) technology. This study focuses on the development of helical plasmonic nanostructures to enhance the SERS effect for both chiral and achiral molecule detection.
To evaluate the efficiency and the structural impact of helical nanostructures in silver nano-helices substrate (AgNHs), our study unveils a remarkable simulation enhancement factor of 1.5×10¹³, achieved through an optimal geometric configuration with a pitch height of 250 nm and a diameter of 0.8 μm. The precision fabrication of these helical nanostructures was realized using Two-Photon Lithography (TPL), with subsequent metal coating applied via Glancing Angle Deposition (GLAD) to construct the AgNHs substrate. Quantitative analysis through Raman spectroscopy revealed an average SERS enhancement factor (EF) of approximately 3.33×10⁶ across various concentrations and analytes.
Our findings reveal that the AgNHs markedly surpass traditional SERS substrates. These results highlight the transformative impact of revolution of nanostructure in SERS substrates and chirality sensing for both academic research and real-world applications.