Materials processing with a tightly focused femtosecond vortex laser pulse

TL;DR

This paper demonstrates the first use of tightly focused femtosecond laser vortex beams for precise material modification, enabling the creation of high-quality, micron-sized ring structures in glass materials.

Contribution

It introduces a novel method of material processing using femtosecond vortex beams with controlled focusing and pulse energy, achieving precise ablation patterns.

Findings

Successfully synthesized double-charge femtosecond vortices.

Achieved micron-scale ring-shaped structures with sub-100 nm uniform grooves.

Demonstrated material modification in fused silica and soda-lime glasses.

Abstract

This letter is the first demonstration of material modification using tightly focused femtosecond laser vortex beams. Double-charge femtosecond vortices were synthesized with the polarization-singularity beam converter described in Ref [1] and then focused using moderate and high numerical aperture optics (viz., NA = 0.45 and 0.9) to ablate fused silica and soda-lime glasses. By controlling the pulse energy we consistently machine high-quality micron-size ring-shaped structures with less than 100 nm uniform groove thickness.