Ge-capped SiGe core optical fibers

Abstract

CO2 laser processing offers the possibility to inscribe structures within glass-clad SiGe-core fibers by altering the spatial distribution of the Si and Ge. Spatial segregation of Ge to the end of a fiber is shown via optical transmission measurements to alter the local bandgap, and the curved end of the fiber focuses the output of a multimode fiber. Scalable fabrication is demonstrated using a commercial CO2 laser engraver for processing of arrays.