Broadband Metamaterial for Invisibility Cloaks & Microscope Lenses
Metamaterials – engineered materials that exhibit properties not found in the natural world – have the potential to control light in new ways, but their performance has been hindered by an inability to function over broad bandwidths of light. Stanford University researchers have now created a broadband metamaterial that more than doubles the range of wavelengths of light that can be manipulated. With adjustments, the researchers believe their new material could lead to invisibility cloaks, or a 'perfect lens' that allows direct observation of an individual protein in a light microscope. All natural materials have a positive index of refraction – the degree to which they refract light. The nanoscale, artificial 'atoms' that make up the metamaterial prism shown in this short video, however, were designed to exhibit a negative index of refraction, and skew the light to the left.