The refractive index of a material defines the angle through which light is bent when it travels between a material and the vacuum. Ordinary materials such as glass have refractive indices between one ...

Physicists are involved in an unusually heated debate over the reality of a new kind of refraction and about the possibility of making perfect lenses. Edwin Cartlidge reports. If you think science is ...

Starting from this unit cell that creates the single negative property, we build two new configurations just by breaking the symmetry in two different ways: either (1) we build a bi-periodic chain by ...