Femtosecond photon echo and four-wave mixing in dye-doped polymer films, semiconductors and heterostructures

Abstract

A review of femtosecond experiments on photon echo (PE) and four-wave mixing (FWM) performed at room temperature is presented. The Weiner-Ippen technique of FWM spectroscopy is demonstrated in dye-doped polymer films (such as polyvinilbutural doped with phthalocyanine), semiconductors (CdS) and heterostructures (GaAs/AlGaAs). The experimental setup used in these experiments is described. The dephasing times are estimated and the relaxation mechanisms are discussed.

Femtosecond correlated photon echo in CdS crystal under two-photon excitation by two pairs of crossed laser beams

“…There is also a theoretical method elaborated by Kobayashi and colleagues [8] allowing the facilitation of the calculations. In the previous work [9], we used both methods in the analysis of the results of our femtosecond experiments.…”

“…Due to the phase matching conditions a significant contribution to the product of two expressions in the square brackets can be made only by the last term in the second factor. Therefore we can rewrite (9) as…”