Sol–gel silica glass-cladding semiconductor-core optical fiber
Résumé
Hybrid optical fibers consisting of glass clad and semiconductor core materials are extensively investigated due
to their interesting properties that make them attractive for several technological applications. Here, we report
on a new approach for the fabrication of such multi-material optical fiber preform using the sol–gel technique. It
consists in mechanically drilling a central hole in a silica xerogel rod, then in filling this hole with a centimeterlength
silicon rod, and finally in densifying the silica glass jacket around the silicon core. By drawing this
preform, a homogenous hybrid rod-type fiber was obtained. The composition and the structural properties of the
pristine silicon rod, of the hybrid preform and of the drawn fiber have been investigated using electron probe
microanalysis, Raman spectroscopy and transmission electron microscopy. We have shown that the silicon core
material preserves its composition and polycrystalline structure all along the fabrication process.