| Title |
Self-organization in thin metal films under laser irradiation / |
| Translation of Title |
Plonų metalų sluoksnių savitvarkos lazerio spinduliuotės poveikyje tyrimas ir modeliavimas. |
| Authors |
Gedvilas, Mindaugas |
| Full Text |
|
| Pages |
99 |
| Keywords [eng] |
Chromium on glass ; laser ablation ; Marangoni convection ; Plateau-Rayleigh instability ; ripple |
| Abstract [eng] |
The aim of this PhD thesis is to find out mechanisms of the ripple initiation and formation in the chromium thin film on the glass substrate. To learn to control the ripple formation and to apply it for fabrication of diffraction gratings. In this thesis, the experimental and theoretical results of new self-organization effect of the metal thin film on the glass substrate under irradiation with a sequence of partially overlapping laser pulses are presented. The method for formation of the regular ripples and results on investigation of diffractive properties of the self-organized gratings is presented. Different types of metals are used in experiments in order to understand the reasons of regular structure formation in chromium film. A diverse behavior of the films under laser irradiation is observed depending on the metal when burst of partially overlapping pulses was applied. Experimental data is compared with simulations based on different physical phenomena in order to develop and confirm a model of ripple formation in thin chromium film under its irradiation with pulses of a nanosecond laser. The Plateau-Rayleigh instability of the cylindrical ridge formation during laser ablation appears to be the most probable process responsible for initiation of the ripple formation. The Marangoni convection of the molten metal from hot areas to cold is the stabilizing process of steady ripple formation. |
| Type |
Doctoral thesis |
| Language |
English |
| Publication date |
2011 |
