Author(s):
1. Milesa Srećković, Elektrotehnički fakultet, Univerzitet u Beogradu, Bulevar Kralja Aleksandra 73, Serbia
2. Aco Janicijević, Tehnološko-metalurški fakultet, Univerzitet u Beogradu, Srbija, Serbia
3. Aleksandar Bugarinović, Telekom, republikaa srpska BiH, Republic of Srpska, Bosnia and Herzegovina

Abstract:
ANALYTICAL AND EXPERIMENTAL APPROACHES TO LASER INTERACTION WITH VARIOUS MATERIALS M. Srećković1, D. Družijanić1, A. Janićijević2, M. Janićijević3, A. Bugarinović4, S. Pantelić1, S. Polić5, 1Faculty of Electrical engineering, Univesity of Belgrade, Serbia, e-mail: esreckov@etf.rs 2Faculty of Metallurgy and Technology, Univesity of Belgrade, Serbia, e-mail: janicaco@tmf.bg.ac.rs 3Metalac A. D., Gornji Milanovac, Kneza Aleksandra 212, Serbia 4Telekom, Republika Srpska, Bosnia and Herzegovina, e-mail: aleksandar.bugarinovic@mtel.ba 5Central Institute for Conservation, Belgrade, Serbia Abstract: The interaction of coherent light with the materials, depending on the selected power diapason (power density), has long been the subject of research. Approaches through formalisms such as thermal, hydro-gasodynamics, similarity models, etc., were further adapted, because the ultra-short pulses had to be included, since different outputs were needed. One of the approaches takes only the relevant parameters to distinguish contributions of the lattice and the electrons into the physical characteristic parameters. Control of experiments for different geometries, types of lasers and materials would advance the models and bring many new parameters. In addition to controlling plasma process and ejected materials, there are still many unknowns and new questions are raised. Exposure times, pulse lengths, non-linear parameter changes, complicate general approaches, and the difference itself appears depending on cw to atto and zepto areas. In addition to our results for Nd3+: YAG lasers and CO2 lasers, experiments with alexandrite laser were included. (The transitions in alexandrite laser requires multiple models.) Here are presented experiments with 755 nm in pulse regime (15 J, 1 Hz, 10 ms and various number of pulses (5-10) for the same target for samples types). The experiments were performed under two polarizations, in which the dependance of the damage shapes and polarization were important. Many models do not include explicitly the polarization of the beam. Only the approaches with generalized Fresnel's formula can approximate basic calculations. Wiedeman-Frantz-Lorentz's law and Lorentz's formulation can be used for decision making for contribution of electrons and the lattice, in physical values (electrical and thermal conductivities, specifical heats, etc.). Thus, it can at least indicate qualitatively the change tendency of the parameters, which will be included in the simulation of modeling interaction. The results of the experiment will be analyzed via optical and electronic microscopies. Computer support for simulations will be performed through Image J, Comsol, Numerics or Zemax and other programs. Various possibilities for descriptions of interaction in those programs were discussed.

Key words:
Keywords: Interaction, polarization, modeling, alexandrite laser

Thematic field:
SYMPOSIUM A - Science of matter, condensed matter and physics of solid states

Date of abstract submission:
31.07.2017.

Conference:
Contemporary Materials 2017 - Savremeni Materijali