Enhanced sensitivity of SPR sensing and imaging using plasmonic nanopillar arrays

We present a 2-dimensional gold nanopillar array, consisting of narrow gaps between the nanopillars, for application in the area of biosensing. Normally incident light can couple directly into plasmonic waveguide modes in these 2-dimensional plasmonic nano-gratings formed by the 2-dimensional array of gold nanopillars. The effect of polarization of the incident light and of the dimensions of the nanopillars on the sensitivity of localized sensing was studied using Rigorous Coupled-Wave Analysis. The results show that the sensitivity of biosensors made from these nanopillar arrays is not polarization dependent. Moreover, varying the structural parameters of the nanopillar array can enable tuning of wavelengths at which biosensing can be carried out.