New Fiber Optic Technology

By twisting fiber optic strands into helical shapes, researchers have created unique structures that can precisely filter, polarize or scatter light. Compatible with standard fiber optic lines, these hair-like structures may replace bulky components in sensors, gyroscopes and other devices. While researchers are still probing the unusual properties of the new fibers, tests show the strands impart a chiral, or "handed," character to light by polarizing photons according to certain physical properties. In conventional optical fibers, light is transmitted from one end to the other through a round core housed within a concentric outer cladding. But, because a circular core does not develop handedness when twisted, the research team wound rectangular-core fibers to create a double helix. When the team tested the twisted fiber, they discovered that some photons left the core and entered the cladding. Photons with the same handedness as the fiber entered the cladding whereas photons with handedness opposite that of the fiber remained in the core. This research was funded both NSF and the National Institute of Standards and Technology Advanced Technology Program.