Scientists at IBM have created a silicon chip that uses a combination of miniature heaters and photonic crystal technology to control the speed of light streams.
Scientists at IBM have created a silicon chip that uses a combination of miniature heaters and photonic crystal technology to control the speed of light streams. The current conductors made of silicon are activated by currents with wavelengths of 1.5 microns - a common wavelength in wireless communication - which can slow down the speed of light by a factor of up to 300.
During the last decade, physicists have resorted to exotic means such as ultra-cold gas atoms and various crystals in order to "slow down" or "speed up" the speed of light. Some groups were able to stop and store light, while others demonstrated bursts of energy with a speed greater than the speed of light in a vacuum. However, if silicon chips can control the speed of light, it will be possible to include these means in microelectronic circuits.
Yuri Vlasov and his colleagues at the YBM Research Center. According to T.G. Watson (IBM TJ Watson Research Center) in New York took a step in this direction by using photonic crystal waveguides made of silicon in order to produce "slow" light. On top of the conductor, which is 250 microns long, patterns of small holes, each 109 nanometers long, are engraved, giving it a high refractive index. The electron bonds function as miniature heaters.
When a current passes through the heater, it heats the conductor, the refractive index changes and the speed of light inside the structure changes. Injecting about 2 milliwatts of electronic power into the system can change the refractive index by a factor of about three to 100 nanoseconds.
IBM's work was carried out following recent studies on the manipulation of the speed of light with the help of optical fibers and semiconductor structures.
