First Demonstration of Imaging by Flat Lens
P. Parimi, W. T. Lu, P. Vodo and S. Sridhar
Nature, V. 426, P. 404 (2003)
The positive refractive index of conventional optical lenses means that they need curved surfaces to form an image, whereas a negative index of refraction allows a flat slab of a material to behave as a lens and focus electromagnetic waves to produce a real image. Here we demonstrate this unique feature of imaging by a flat lens, using the phenomenon of negative refraction in a photonic crystalline material. The key advance that enabled us to make this observation lies in the design of a photonic crystal with suitable dispersion characteristics to achieve negative refraction over a wide range of angles.
This work was selected for Breakthrough #8 of 2003 by Science and received the President’s Aspiration Award.