Fluorescence spectra and fluorescence lifetime of colloidal solution of an organic dye, bis-MSB, and third-order optical nonlinearities of its excitons

摘要

We made microparticles of an organic dye, bis-MSB, and measured fluorescence spectrum, fluorescence lifetime, and the third-order optical nonlinearities of exciton of the microparticles. We evaluated that an effective X~((3)) of excitons of bis-MSB in colloidal solution was about 1/23 of that of the excited dye molecule from the observed DFWM signal intensity. Taking the concentration of excitons of the dye in colloidal solution into the consideration, we concluded that the value of molecular hyperpolarizability for an exciton in microparticle should be about one third of that for an excited state of the dye in solution.