A property of a material that changes the speed of light, computed as the ratio of the speed of light in a vacuum to the speed of light through the material. When light travels at an angle between two ...

Introduction If you pour water into a clear glass, what color is it? It's clear, right? But what happens if you try to look through it to see the world on the other side of the glass? It looks a ...

Waves close wavesVibrations that transfer energy from place to place without the transference of matter. - including sound and light - can be reflected at the boundary between two different materials.

For the first time, physicists have devised a way to make visible light travel in the opposite direction that it normally bends when passing from one material to another, like from air through water ...

Light bends when travelling through a concentration gradient of sugar in water. The top layer of liquid is pure water while the bottom layer is concentrated sugar water. In these layers, there is no ...

By combining two fundamentally different microscopy techniques, researchers can now measure the optical properties of a ...

Physicists at Harvard University in the US have built a silicon waveguide that exhibits a refractive index of, or close to, zero when operating at near-infrared telecom wavelengths. The waveguide can ...