High-speed manufacturing of highly regular femtosecond laser-induced periodic surface structures: Physical origin of regularity

摘要: Highly regular laser-induced periodic surface structures (HR-LIPSS) have been fabricated on surfaces of Mo, steel alloy and Ti at a record processing speed large areas with regularity in the obtained sub-wavelength structures. The physical mechanisms governing LIPSS are identified linked decay length (i.e. mean free path) excited electromagnetic waves (SEWs). dispersion orientation angle well correlates SEWs length: shorter this length, more LIPSS. A material dependent criterion for obtaining HR-LIPSS is proposed variety metallic materials. It has found that decreasing spot size close to SEW key covering several cm2 by few seconds. Theoretical predictions suggest reducing laser wavelength can provide possibility production principally any metal. This new achievement unprecedented level control over structure formation makes laser-writing technology be flexible, robust and, hence, highly competitive advanced industrial applications based nanostructuring.