Manipulation of multidimensional plasmonic spectra for information storage

We demonstrate a concept of optical data storage through plasmonic resonances of metallic nanostructures. Metallic nanostructures exhibit strong variations in their reflectance and/or transmittance spectra due to surface plasmon polariton resonances. We study the variations in spectra through $50×50$ arrays of repeated unit cells covering a total area of $∼50×50μm2$⁠. Each cell contains ten different nanofeatures, such as an ellipse, a ring, a circle, a triangle, a square, etc. The size of each unit-cell is $500×500nm2$⁠, and the periodicity is $1.0μm$⁠. The variations in spectra are obvious enough to be distinguished and then retrieved.