Gold nanorings as substrates for surface-enhanced Raman scattering

Area of Science:

• Plasmonics
• Nanophotonics
• Spectroscopy

Background:

• Surface-enhanced Raman scattering (SERS) is a powerful technique for molecular detection.
• Noble metal nanostructures are crucial for generating localized surface plasmon resonances (LSPRs) that enhance Raman signals.
• The geometry of nanostructures significantly influences their plasmonic properties and SERS efficiency.

Purpose of the Study:

• To investigate the SERS performance of gold nanoring substrates.
• To compare the enhancement factors of single nanorings, nanoring dimers, and nanodisk dimers.
• To validate experimental SERS enhancement factors with electromagnetic simulations.

Main Methods:

• Fabrication of gold nanoring and nanodisk dimer arrays.
• Measurement of SERS enhancement factors using model analytes.
• Electromagnetic simulations to predict and compare enhancement factors.

Main Results:

• Single gold nanorings achieved an average SERS enhancement factor of 4.2 x 10^6.
• The SERS performance of nanoring arrays was evaluated and compared to nanodisk dimers.
• Experimental enhancement factors showed good agreement with simulated electromagnetic predictions.

Conclusions:

• Gold nanorings are highly effective substrates for SERS applications.
• The nanostructure geometry plays a critical role in optimizing SERS enhancement.
• Simulations provide a reliable method for predicting and understanding SERS enhancement mechanisms.