We calculate the susceptibility responsible for self-focusing in SF6 in two parts, the ν3-ladder contribution and the quasi-continuum contribution. Our ν3-ladder vibrational model is a classical triply degenerate anharmonic oscillator in the Cartesian basis with the anharmonicity parameters chosen to be consistent with the latest spectroscopic analysis of the 3ν3-overtone spectrum. The rotational structure is represented by a distribution of these oscillators in which the distribution is chosen to correspond to the spectrum of the ν3 fundamental. Using our previously published model, we find that the quasi-continuum contribution is much smaller than the ν3-ladder contribution to the susceptibility and always decreases with increasing laser energy. We find that the ν3 ladder is entirely responsible for self-focusing in SF6. The susceptibility curves show qualitative agreement with the 300-K self-focusing data of Nowak and Ham [Opt. Lett. 6, 185 (1981)] at CO2 P(28), P(20), and P(10) in SF6. Calculations with a two-dimensional diffraction-propagation code show good quantitative agreement with the Nowak and Ham data at CO2 P(20) and P(10).
© 1981 Optical Society of AmericaFull Article | PDF Article
OSA Recommended Articles
J. Opt. Soc. Am. B 9(11) 2100-2106 (1992)
Xueming Yang, C. A. Rogaski, and A. M. Wodtke
J. Opt. Soc. Am. B 7(9) 1835-1850 (1990)
Harold W. Galbraith
Opt. Lett. 3(4) 154-155 (1978)