One and two-photon picosecond excitation dynamics of the singlet states of a tetraphenyl-diamine derivative in solution

We report on nonlinear absorption measurements of a tetraphenyl-diamine dye which was developed to be used as a transparent two-photon-type molecular material for optical limiting applications in the visible range. The excited state properties which are relevant to the process are investigated experimentally using picosecond nonlinear optical Kerr ellipsometry for differential absorption cross section monitoring. Results of the picosecond one- and two-photon absorption dynamics are presented. Time-resolved excited state absorption properties are discussed in terms of the optical limiting application.