Formation of Microtower Structures on Liquid Metal Surfaces under Nanosecond Laser Ablation

摘要

Formation of stable micro-protrusions and microstructures ("microtowers") on surface of liquid metals during multipulse irradiation by UV and IR lasers in different ambient gases was discovered. The rates of the structure formation have been measured which can reach 5-20 μm/pulse depending on the metal and ambient gas sort. Single micro-protrusions 1-2 mm in length were formed with diameter approximately two times greater than the focal spot size. The possibility to control the micro structure shape is shown and their potential applications are demonstrated.