NEC Research Institute Grows Opals On a Chip
A research scientist friend of mine, prone to messing with those who base their life decisions on sound Bytes of scientific knowledge, frequently shuts down folks who say their diet is "all-natural" or "organic" by saying "Cyanide is all natural" and "Poison mushrooms are organic." I'm not sure why this story brought my science geek friend to mind except that science, technology, and nature intersect in many ways that aren't always immediately apparent. The fact is that many of the ingredients for our high tech gadgets come from good old Mother Nature. This development from NEC Research Institute (NECI) and Princeton University is an example of the intersection of nature and technology that, I have to admit, seems more fascinating that making processors out of sand. The two groups just announced a breakthrough in the development of photonic band gap crystals by demonstrating a way to obtain these materials, which can be used to create photonic devices for telecommunication and computing.
Here's the geekware. Photonic band gap crystals are materials that are bout 1/100th the width of a human hair. When light strikes these structures, it can be reflected in new directions. So, photonic band gap crystals allow light to be manipulated as it travels through the material. Photonic band gap crystals might be able to be used to build all-optical integrated circuits. The NEC and Princeton folks figure that, since most telephone and internet traffic is transmitted as pulses of light along optical fibers, photonic circuits could replace the large and expensive devices that now control signals over optical networks.
The approach the scientists used begins by emulating a natural process, the formation of gemstone opals. Under certain geological conditions, nature spontaneously forms extremely small silica spheres. When millions of these micrometer-scale marbles are stacked on top of each other, a natural opal is created. Prior work had shown that not only could such opals be grown in the laboratory, but that they could be used to make photonic band gap crystals. By filling the space between the spheres with a semiconductor and then selectively removing the spheres, an extremely porous material, referred to as an inverted opal, can be made. NECI used this "natural assembly'" approach to form planar synthetic opals directly on a silicon wafer. NECI says the next challenge will be to use the materials to make an actual device. It will, to a certain extent, be both natural and organic (organized or arranged as a system of related parts).