“HybridFiber: Localized in-line precipitation of metallic nanostructures in hybrid optical fiber”

German Science Foundation

Optical waveguides (WGs) represent key elements in modern photonic systems. Light guidance in such WGs is achieved by transversely confining the electromagnetic (EM) wave by a dielectric gradient. Such a gradient can readily be obtained in a core-cladding fiber geometry. The confinement induces formation of discrete optical modes with precise “quantum numbers” – similar to the hybridization of atomic orbitals in molecular chemistry. The most prominent WG example is the silica-based optical fiber, which is the backbone of today’s telecommunication technology and mostly operates at near-infrared (NIR) wavelengths or in the visible (VIS) spectral range. Besides guiding light optical fibers have found application in light generation schemes such as fiber lasers or supercontinuum generation (SCG). Many of the mentioned applications require precise tuning of the optical properties of guided modes, which is in many cases not possible to achieve with current fabrication technology and/or state-of-the-art materials. For instance, a crucial parameter which is very difficult to tune during fabrication is the group-velocity dispersion (GVD) which was shown to be key to optimize SCG in fiber WGs in terms of spectral broadness and density. The present project aims to solve the fabrication limits from a material-science perspective by exploiting nanoparticle-enhanced (NP-enhanced) glasses which provide tunability of the photonic device properties after the actual device fabrication. This is a collaboration with Prof. Markus A. Schmidt, IPHT Jena.