Preliminary results on self-trapped filaments in different liquids and liquid mixtures are reported. It is shown that stimulated Raman and Brillouin scattering is probably not responsible for the filament formation. Further work is needed to determine whether Kerr effect or field-induced phase transition is the principal mechanism for self-trapping. Difference-frequency generation in the submillimeter region from quartz and LiNbO3 by beating of two ruby laser beams is reported. The difference-frequency is tunable through thermal tuning of the laser frequencies. This is the first coherent, tunable, far-infrared pulse generator ever constructed.
Semiannual technical summary rept. 1 Jan-30 May 1968