Bespoke photonic devices using ultrafast laser driven ion migration in glasses

This Review provides an exhaustive and detailed description of ion migration phenomena which occur inside transparent dielectric media due to the interaction with intense ultrashort pulses. The paper differentiates various processes underlying the ion migration influenced by simultaneous heat accumulation and diffusion. The femtosecond laser induced temperature distribution, the major driving force of ions in dielectrics, is described in detail. This discussion is based on three meticulous analysis methods including the thermal modification of transparent dielectrics at various ambient temperatures, numerical simulations and comparison with direct observation of the light-matter interaction and micro-Raman spectroscopy. The ion migration phenomena studied have been triggered in four different configurations: at low repetition and high repetition rates, and observations perpendicular and parallel to the laser irradiation direction. Inspired by this research, potential applications are highlighted including space-selective phase separation, a laser-based ion exchange fabrication method and optical micropipetting by tailoring the plasma profile.