Metamaterial Waveguide 2 (IMAGE) Georgia Institute of Technology Caption Georgia Tech graduate student Shoufeng Lan holds a metamaterial waveguide located at the center of a silicon chip, wired to an external circuit. Lan is first author of a paper reporting on the creation of a nonlinear material that has opposite refractive indices at the fundamental and harmonic frequencies of light. Credit Courtesy of John Toon, Georgia Tech Usage Restrictions None License Licensed content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.