Flattened mode cylindrical and ribbon fibers and amplifiers

摘要

Large area mode operation of fibers with Strehl-ratio-optimizing flat-topped output beams is enabled. The approach entails both refractive index profile engineering and gain profile engineering to realize fiber structures that while supporting several transverse modes only allow a preferred flat-topped mode to lase due to the modal gain discrimination that is engineered in during the fabrication of the structure.