Self-focusing arrest of femtosecond laser pulses in air at different pressures.

Max-Planck-Institut für Physik komplexer Systeme, Nöthnitzer Strasse 38, D-01187 Dresden, Germany.
Physical Review E (Impact Factor: 2.31). 08/2006; 74(1 Pt 2):016602. DOI: 10.1103/PhysRevE.74.016602
Source: PubMed

ABSTRACT We study analytically and numerically the self-focusing arrest of femtosecond laser pulses in air at different pressures in the presence of an external focus lens. Analytical estimations as well as results of simulations show that the intensity at which the self-focusing arrest occurs is almost independent of the gas pressure. However, a dependence on the temperature is found. The Raman effect is taken into account, and an estimation of the intensity inside of filaments at high altitudes is given.

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