Researchers at Duke University in the US have determined the theoretical limits of how much electromagnetic energy a transparent material can absorb. This can help researchers optimize device designs in the future, but it has also ended a 20-year wait for a mathematical solution to the problem.
Rozanov lined the transparent material with a piece of metal on one side. This helped him figure out the range of wavelengths that would get absorbed in the material since the metal lining either reflected or absorbed the light that came its way. More importantly, Rozanov had a clever trick that made the solution work. He worked with wavelengths instead of frequency. The metal approach failed to solve the problem when researchers worked with frequency.Willie Padilla, an electrical and computer engineering professor at Duke University, sought to solve this problem to make better devices.