  This thesis is focused on numerical simulations of the laser interaction with
porous materials. A possibility of well-controlled processing is particularly
important for the laser based micro-structuring of porous glass and
nano-machining of semiconducting porous materials in the presence of metallic
nanoparticles. To understand the periodic micro-void structures produced inside
porous glass by femtosecond laser pulses, a detailed numerical thermodynamic
analysis was performed. The calculation results show the possibility to control
laser micro-machining in volume of SiO2. The obtained characteristic dimensions
of the structures correlate with the experimental results. Comparing to the
porous glass, the mesoporous TiO2 films loaded by Ag ions and nanoparticles
support localized plasmon resonances. To identify the optimum parameters of the
continuous-wave laser, a multi-physical model considering Ag nanoparticle
growth, photo-oxidation, reduction was developed. The performed simulations
show that the laser writing speed controls the Ag nanoparticles size. The
thermally activated fast growth followed by the photo-oxidation was found to be
the main reason for the writing speed-dependent size-change and temperature
rises. Writing of mesoporous TiO2 films loaded with Ag nanoparticles by a
pulsed laser is, furthermore, promising to provide additional possibilities in
the generation of two kinds of nanostructures: laser-induced periodic surface
grooves and Ag nanogratingsinside the TiO2 film. To better understand the
effects of a pulsed laser, two multi-pulses models are developed to simulate
the Ag nanoparticle growth. The obtained results provided new insights into
laser micro-processing of porous material and better laser controlling over
nanostructuring in porous semiconducting films loaded with metallic
nanoparticles.
