One-step micro-modification of optical properties in silver-doped zinc phosphate glasses by femtosecond direct laser writing

We demonstrate the possibility of joint formation of fluorescent silver clusters and plasmonic silver nanoparticles spatially confined in micron-sized domains by the one-step femtosecond direct laser writing (DLW) without subsequent heat treatment in zinc phosphate glasses with different concentration of silver. We show that DLW in glass induces local micro-modification of optical properties resulted in the appearance of luminescence, absorption and form birefringence in domains. Variation of laser pulse energy allows controlling the micro-modification process and tuning of optical properties. We propose a possible mechanism for observed phenomena that includes local chemical redistribution of glass network modifiers during DLW process. We believe that ability to form complex 3D shapes of luminescent, plasmonic and birefringent structures embedded in dielectric transparent glass materials opens new routes for the design of nanophotonic devices and multidimensional optical memory.