Alfresco fabrication

Researchers at the US Department of Energy’s

are making 3D photonic band gap crystals four millimetres square and 12 layers high without benefit of a “clean room” environment or the multimillion dollar equipment traditionally required to create such structures.

The fundamental research, supported by the Basic Energy Sciences Office of the DOE’s Office of Science, holds potential for significantly reducing the costs associated with fabricating PBG crystals, devices that make it possible to route, manipulate and modify the properties of light.

PBG crystals can permit or block the transmission of light of certain frequencies in all directions. This characteristic makes them especially promising for applications in the field of optical communications, where the push is on to create a photonic crystal within a single computer chip.

The research path to that goal is an expensive one. But Kai-Ming Ho, an Ames Laboratory senior physicist, and Kristen Constant, an Iowa State University associate professor of materials science and engineering, and their co-workers are easing the way by fabricating PBG crystal microstructures in the open air, something that has never been done before.