The continued development of optical communications requires fast information processing. Therefore, ultrafast, all-optical systems and switches for basic processing at both ends of an optical transmission line are replacing electronic systems. However, there are speed and fabrication limits on present all-optical switches imposed by the properties of the materials presently used. This technology provides an improved ultrafast high sensitivity all-optical switch made from a single-walled carbon nanotube.

The photonic and optoelectronic communities have long been interested in the development of tunable delay systems for optical pulses. The various systems developed suffer from shortcomings such as limited delay range for high speed devices, low duty cycles and nonlinearity in optical path-length change, the inability to provide tens of centimeter scanning range and a repetition rate in the hundreds of hertz range, and low temporal resolution and optical loss.