Optimal Aspect Ratio and Excitation Spectral Region of LSPR Sensors Using Individual Au Dimmeric Nanoplates

Both the excitation wavelength and aspect ratioARare key parameters controlling the refractive index sensitivity performances of plasmonic sensors of individual Au nanoplate dimmers. In this work, the refractive index sensitivity factorSand figure of meritFOMof individual Au dimmeric nanoplate sensors with different plate cross-sections were investigated numerically as functions ofARand their resonant wavelength of dipolar localized surface plasmons. Their optimalFOMand corresponding optimalARand excitation spectral region for plasmonic sensing are predicted simultaneously. The effects of the plate cross-section shape and near-filed coupling between components within each dimmer onSandFOMare also discussed. The present work holds great promise for choosing componentARand excitation wavelength for Au dimmeric nanoplate applications in optical sensing and detection.