Investigation of benzoporphyrin and azulenic compounds by two-dimensional z-scan technique

Abstract

A two-dimensional Z-scan technique employing a CCD camera was used to study the nonlinear optical parameters of materials. Using the known beam distribution at the lens plane, measured by the CCD camera, and the split step beam propagation method, we simulate the evolution of the beam profile within the sample. This technique may be applied to any arbitrary beam distribution and sample thickness. We applied our two- dimensional Z-scan technique for the investigation of zinc tetraphenyltetrabenzoporphyrin and three azulene-containing donor-acceptor compounds. It was found that some samples exhibit strong nonlinear refraction while others show strong nonlinear absorption. The use of these materials in optical limiting devices is discussed.