Speaker
Description
Selective laser-induced etching (SLE) relies on ultrafast laser modification of glass followed by selective chemical removal, yet the transient mechanisms that connect laser exposure to the final etched surface morphology remain insufficiently understood. A key open question is to what extent the periodic and quasi-periodic surface patterns frequently observed after etching originate from the ultrafast laser–matter interaction itself, from cumulative inter-pulse or inter-line dynamics, or from subsequent etching-driven roughness evolution.
In this work, we investigate surface topography formation in SLE-processed fused silica by combining systematic laser-parameter studies, controlled chemical etching, surface characterization, and time-resolved pump–probe microscopy. Laser writing strategies are varied to modify the spatial and temporal overlap of subsequent pulses and lines. The resulting surfaces are analyzed after etching to quantify roughness evolution, micro- and sub-micrometer feature formation, and the possible existence of an asymptotic roughness limit. A central part of the study is a pump–probe investigation of transient optical responses in fused silica after ultrafast excitation. The dynamics from ps to µs time scales are correlated with the etched surface morphology to identify which transient processes are likely to survive into permanent, etch-revealed structures.
This combined ultrafast-diagnostics and surface-metrology approach provides a route toward understanding how pulse-to-pulse material response governs morphology formation in SLE. Ultimately, the goal is to move from empirical laser-etching parameter selection toward predictive control of surface topography in three-dimensional glass microfabrication.