A research team led by Koray Aydin, who serves as Assistant Professor of electrical engineering and computer science at the McCormick School of Engineering and Applied Science of the Northwestern University has created a composite metamaterial, which absorbs broad array of light wavelengths, paving the way to develop economic and efficient solar cell technology.
The research team has published its research paper titled ‘Broadband polarization-independent resonant light absorption using ultrathin plasmonic super absorbers,’ in the Nature Communications journal.
The research team has utilized silicon oxide and metal, two unusual materials, which do not absorb light of their own to develop intricate, nanoscale trapezoid-shaped metal gratings that can capture a broad array of visible light. Aydin commented that the combination of the two materials at the nanoscale demonstrates superior absorption rates.
The specially shaped grating trapped an extensive range of wavelengths caused by local optical resonances, which make the light to stay for more time within the material until it gets captured. The innovative material can also capture light from various angles, a key aspect in designing efficient solar cells.
This research work is not directly related with solar cell technology, as silicon oxide and metal cannot transform light to electricity. Actually, the photons are transformed to heat and allow novel methods to manipulate the flow of the heat at the nanoscale. Aydin commented that by replicating the novel trapezoid shape in semiconducting materials, the technology can be used for the fabrication of thinner, less-expensive and high-efficiency solar cells.