Mirror fabrication on optical fibres using maskless excimer laser-assisted methods

This work deals with two novel methods for the fabrication of mirrors on single mode optical fibres (SiO2 doped with GeO2 in the core). In both procedures, XeCl excimer laser pulses were utilised for either the activation—for consecutive chemical metallisation—of the core (additive process) or the ablative patterning of the preliminary chemically deposited metal film (subtractive method). In situ reflectance measurements (at 1350 nm) allowed us to tailor the metal growth and reach the proper mirror thickness. Both methods were found to be suited to create reflective copper coatings with maximum relative reflectivity of ∼9 dB. Optical microscopy has been involved in the characterisation of Cu mirrors.