Hyuck Choo, Assistant Professor of Electrical Engineering, and Postdoctoral Scholar Myung-Ki Kim have invented a light-focusing device that may lead to applications in computing, communications, and imaging. This new kind of waveguide is made of amorphous silicon dioxide and is covered in a thin layer of gold. Just under two microns long, the device is a rectangular box that tapers to a point at one end. With the new device, light can ultimately be focused in three dimensions, producing a point a few nanometers across, and using half of the light that's sent through, Choo says. (Focusing the light into a slightly bigger spot, 14 by 80 nanometers in size, boosts the efficiency to 70 percent). The key feature behind the device's focusing ability and efficiency, he says, is its unique design and shape. [Caltech Release and Video]
