“ Nanostructured surfaces ”

Numerical and analytical prediction of the process of destructive laser-stimulated action on the material surface
L.V. Shmeleva, A.D. Suprun, S.M. Naumenko
 Department of Theoretical Physics, Faculty of Physics, Taras Shevchenko National University of Kyiv. Volodymyrska Street, 64/13, Kyiv-01601, Ukraine. 
E-mail: lshmel@univ.kiev.ua 

Laser radiation ensures getting the limiting values of many parameters. These are the power density in the focusing zone, the realized temperature in the action zone, etc. Laser processing can be applied to almost all materials, independently of their hardness and viscosity. Those are metals, hard alloys, ceramics, glass, plastics, rubbers, semiconductor materials, precious stones, biological materials.  Therefore, the use of laser technology is relevant in many industries: from medicine to the military industry.
The practical use of high-power lasers requires big material and energy costs.  Therefore, theoretical and numerical prediction of the results of laser action on different surfaces of materials does not lose its relevance.
Research is based primarily on developments that allow to the calculation of conditions that delimit the three types of surface treatment. That is non-destructive processing; destructive treatment with the appearance of surface melting; destructive treatment without melting.
For many uses, processing without melting of the irradiated substance is interesting, as it is more accurate. This task involves studying the dynamics of baro- and thermo- indicators on the irradiated surface until the moment of destruction beginning non-destructive effects and tracking these indicators in the process of destruction itself.  An algorithm that allow to modeling all the process irradiation developed. The algorithm maximally takes into account the possible physical mechanisms of interaction of radiation with matter. Moreover, the use of the results obtained for non-destructive effects is important for correcting the operation of the SPR sensors. And all algorithm makes it possible to adequately simulate laser-stimulated surface destruction. The model allows varying the pulse duration, electromagnetic radiation flux, radiation frequency, as well as the type of processed material.