Waveguides in Ni-doped glass and glass–ceramic written with a 1 kHz femtosecond laser

• We wrote waveguides in Ni doped glass and glass–ceramic by femtosecond laser.
• Waveguides can be erased by annealing the glass, but not the glass–ceramic.
• Ni nanoparticles were created during the waveguide writing.
• Ni had more long luminescence lifetime components in the waveguide than in the glass.

We report waveguides in Ni-doped Li2O–Ga2O3–SiO2 (Ni:LGS) glass and glass–ceramic (GC) fabricated with a femtosecond (fs) laser with repetition rate of 1 kHz. When the glass is annealed to form a GC, the waveguides are erased. However, in the GC the waveguides are not erased by annealing. In Ni:LGS GC a 415 nm absorption band was created by fs laser waveguide writing due to the creation of Ni nanoparticles with an estimated diameter of a few nm. Raman and photoluminescence spectra of the bulk and waveguide structures were indistinguishable; however, fluorescence decay profiles indicated more long lifetime components in the waveguide compared to the bulk.