Nonlinear optical elements formation in colloids of quantum dots under femtosecond laser pulses

In this article, the formation and evolution of Gaussian beam lateral intensity distribution after passing through a colloidal CdSe/ZnSe quantum dots and metalloorganic Ag/J aggregate nanoparticles are discussed. This transformation appears as cone-shaped beams formation and series of thick interference rings. The second harmonic of Titan-Sapphires femtosecond laser with pulse duration about 100 fs and 404 nm wavelength is used as a Gaussian beam source. Typical time for establishing of steady-state beam intensity distribution pattern after passing nonlinear media is about 100 ms and concurs with typical time of trap luminescence both single quantum dots and metallographic particles under CW laser.