Optical fiber sensors have been used for a variety of sensing applications such as displacement, temperature, and pressure. They have several distinct advantages such as small size, high accuracy, and freedom from radio frequency and electromagnetic interference as well as inherent safety. An application that is quite important is the remote sensing of magnetic fields or current for both industrial and military uses. Particularly, in harsh environments such as plasma fusion, fiber-optic current sensing would represent a significant improvement over existing measurement approaches. The program will use a developmental approach to achieve a magnetic field sensing optical fiber. By doping the fiber with special chemicals, it will exhibit the Faraday effect in the presence of a field. The sensitivity of the fiber is proportional to the Verdet constant, which increases with increasing dopant level. For this program, the dopant is terbium oxide. The program is to develop a high Verdet constant fiber with low optical loss and good mechanical properties.Anticipated Results/Potential Commercial Applications as described by the awardee:The anticipated result is a remote magnetic field (current) sensor that can be used in utility applications such as current measurement in electric power generation and transmission. It can also be used for current measurements in high energy plasma diagnostics.
