Asymmetric surface lattice resonances in the gold nanodisk array for highly sensitive refractive index sensing

In this study, we demonstrate the sensing of refractive index through asymmetric surface lattice resonances (a-SLRs) in an array of gold nanodisks (AuNDs), showing significant alterations in transmission spectra at the a-SLRs and the shift of resonance wavelengths in response to changes in the refractive index of the surrounding media. We investigate the sensitivity of our approach by utilizing a water-glycerol mixture with different composition ratios, illustrating that the AuND array with the a-SLRs exhibits twice the sensitivity compared to the single AuND relying on localized surface plasmon resonance. Furthermore, the angle-dependent transmission spectra are examined to assess the feasibility of the AuND array with the a-SLRs for sensing applications.