2-PHOTON ABSORPTION AND OPTICAL-LIMITING PROPERTIES OF NOVEL ORGANIC-COMPOUNDS

The optical-limiting behavior and two-photon absorption properties of four novel organic compound solutions in tetrahydrofuran have been inv estigated. An ultrashort laser source with 0.5-ps pulse width and 602- nm wavelength was employed. The transmissivities of the various 1-cm-t hick solution samples have been measured as a function of the beam int ensity as well as of the solute concentration. The measured results ca n be fitted on the assumption that two-photon absorption is the only p redominant mechanism causing the observed optical-limiting behavior. B ased on the intensity-dependent transmissivity measurements, the molec ular two-photon absorption coefficients for the four compounds are pre sented.