It could lead to better computers in the future

Oct 9, 2009 08:09 GMT  ·  By
Front row: John Joannopoulos (right) and Marin Soljacic / Back row: Zheng Wang (right) and Yidong Chong
   Front row: John Joannopoulos (right) and Marin Soljacic / Back row: Zheng Wang (right) and Yidong Chong

The reason why we are able to see objects around us is because photons traveling through the atmosphere readily bounce off obstacles in their path. Some of them enter our eyes, and leave their impressions on the retina, which then transforms the data in electrical impulses and sends them to the brain, for analysis and conversion. Now, MIT experts have put a dent in the way light usually moves, by creating a type of microwave light that can flow losslessly around objects and other obstacles.

Engineers at the Massachusetts Institute of Technology (MIT) have recently announced that they have managed to create the innovative type of light that could be used in the not-so-distant future to create simple, one-way light connections inside computers, allowing them to work faster and more efficiently. In nature, light is permitted to travel both ways. If a beam is shone on an object, then its reflection will travel backwards, along the same path, PhysOrg reports.

“The very fact that reflected beams are allowed to exist, combined with the fact that light at least partially reflects from most objects it encounters, makes optical reflections ubiquitous in nature,” the senior author of a study detailing the find, MIT Physics Professor Marin Soljacic, explains. He conducted the research alongside MIT colleagues Dr. Zheng Wang, Dr. Yidong Chong, and Professor John Joannopoulos. The way they achieved no backwards light reflection was through the use of topological photonic crystals, which, apparently, did not allow photons to be reflected on the same path they came from.

Wang explains that, “We have now found a way to make light travel without bouncing back, by shining it through an array of small ceramic rods placed in a strong magnetic field.” Chong adds, “Once a particular forward direction of the light travel is chosen, no backward travel is permitted.” As it bends and swirls around obstacles, the light exhibits no dissipation, and the photons making it up maintain all of their properties, the team points out. “Loosely speaking the waveguide acts as a perfect cloak of the defect or obstacle in the path of the light; the only difference is a phase shift of the guided light,” Joannopoulos concludes.