Air-guiding Photonic Bandgap Fibers

Photonic bandgap fibers that guide light in an air core have attracted much interest since their first demonstration in 1999. The prospect of low-loss guiding of light in air has importance for a multitude of applications, such as data transmission, gas sensors, dispersion compensation and guiding of high-power pulses. The low overlap between light and glass affects both the loss and nonlinear properties of the fiber. At the same time, the strong overlap between light and air provides a mean for creating convenient gas-filled devices with extremely long interaction lengths. In this project, the basic transmission characteristics of the fiber type are presented. Then the novel dispersion properties are discussed and utilized in a chirped-pulse amplification application. Attenuation mechanisms are introduced to understand the fundamental limits that apply. In order for these fibers to reach broad use in the industry, termination solutions must be available. Therefore, splicing and connectorization is demonstrated. Also of great importance for practical use is the fibers sensitivity to macrobending, which is also studied. Finally, other applications, such as the use for gas-filled wavelength references are demonstrated.