Researchers from Stanford University in California have developed a prism-like silicon device that can split a beam of light into different colors and bend the light at right angles. The device has potential future applications in computing to transmit data faster and more efficiently than electricity. They describe the device as an optical link – silicon etched with a pattern that resembles a bar code. When a beam of light shines at the silicon device, two different wavelengths of light split off at right angles to the input, forming a T shape. Light can carry more data while taking less energy to transmit photons than electrons.The device was made by etching a tiny bar-code-like pattern into silicon. The pattern splits light, similar to how a prism works. The pattern alternates strips of silicon and gaps of air in a specific way, which takes advantage of the fact that as light passes from one medium to the next, some light is reflected and some is transmitted. When light traveled through the silicon bar code, the reflected light interfered with the transmitted light in complicated ways. The device is designed such that the bar code makes use of the interference by directing one wavelength to go left and a different wavelength to go right.
Source: Stanford University