A team of researchers at Lehigh University have confirmed the rainbow trapping effect, to show that plasmonic structures can decelerate light waves across various wavelengths.
The team concentrated ion rays to fit a range of increasingly deeper and nano sized groove into a thin silver sheet. The grooves or nano-gratings reduced the speed of each light wavelength when light was beamed over the structure, imprisoning each color of the rainbow at various points on the grating. This development could help enhance data storage, optical data processing, solar cells and bio sensors. Photons could enhance the capacity of data storage platforms and accelerate processing of visual information.
A metallic surface was needed to develop nanoscale gratings with grooves of varying depths. This changes the properties of the nano patterned surface called Surface Dispersion Engineering. The light waves on the broadband surface are imprisoned along this plasmonic surface at a different groove depth causing a rainbow.
Light of various wavelengths in the 500-700nm region was imprisoned at different spots on the grating. The nanopattern gratings needed to be milled into 150nm rectangular grooves 520nm apart from each other on the surface of a 300-nm-thick silver sheet.