Characterization of Novel Optical Limiters

We report on the nonlinear response of III-V semiconductors and platinum-based dyes. The strong two-photon absorption of these materials results in a nonlinear response to increasing light intensity, resulting in self-focusing as well as increased absorption. We investigated p-type GaSb and GaAs in the SWIR and platinum-containing dyes at 532 nm using 10 ns pulses. We report the nonlinear index of refraction and the two-photon absorption coefficients of these materials using the z-scan technique. This study will help inform the ongoing assessment of these materials as passive optical limiters and the development of new materials.