Femtosecond direct laser writing in silicate glasses doped with silver and cadmium sulfide

Femtosecond direct laser writing (DLW) in oxide glasses doped with photosensitive agents (noble metals and semiconductors) opens new routes for precise space-selective tuning of material properties and development of functional photonic devices including integrated waveguides, optical switches, and volume optical memory. In this study, we showed how DLW can be used for the spatially-selective formation of micron-sized luminescent domains in the bulk of Ag-doped and CdS-doped silicate glasses. Multiphoton ionization caused by DLW leads to local heating of glass in the focal point, which initiates the precipitation and growth of luminescent Ag nanoclusters and CdS quantum dots in the periphery of the domains. The luminescence intensity of the formed domains depends on the laser exposure parameters, such as pulse energy and number of pulses that can be used in the future for multilevel optical data recording.