Numerical modelling of laser filamentation

We report the development of a model written in the COMSOL multi-physics environment to simulate the onset and shortrange propagation of laser filaments in standard atmospheres at sea-level and 10 km altitude. We show excellent agreement with analytical and open-source experimental data for the initial collapse distance of the laser, as well as the free carrier density of the resulting plasma. Limitations of the model are presented as well as the potential for further development, including the incorporation of additional physics to study the effect of filamentation on radio frequency and optical propagation.