Author: MIGLĖ MACKEVIČIŪTĖ
Dissertation title: Efficient and fast glass cutting using laser bursts
Fields of science: Material engineering T008
Scientific supervisor: dr. Paulius Gečys
Defence of the dissertation: 24 October 2025
SUMMARY: This work aimed to investigate the impact of laser burst mode on bottom-up cutting of glass, filament-induced volumetric modifications, and its application in scribing. Bottom-up cutting of soda-lime glass using GHz bursts of picosecond pulses allowed reaching high cutting efficiency due to the material being removed via cracking, indicated by the µm-sized ablation products. High-speed cutting regime comes with an inferior cutting quality. However, it is demonstrated that by varying the number of pulses per burst, it is possible to apply both high-throughput and high-quality processing regimes to the same sample, thus maintaining a high processing speed with excellent quality. Bursts of ultrashort pulses were also used for volumetric modification formation. Volumetric single-shot modifications with cracks were formed in fused silica and soda-lime glass using low focusing conditions (NA ~0.04) and laser bursts. A novel method for controlling the direction of cracks via laser polarization was established and applied to scribe 1.1 mm-thick soda-lime glass. The distance between the modifications and, thus, the scribing speed were increased by aligning the cracks along the scribing line. Stable separation of samples scribed at speeds of up to 10 m/s was achieved using a galvanometer scanner and a telecentric f-theta lens system.