Optical limiting properties of two phthalocyanines using 1064-nm laser in solution

Phthalocyanines are promising molecules which present very attractive properties for nonlinear optical applications. The optical limiting performances of copper phthalocyanine and polychloro copper phthalocyanine have been investigated using 1064-nm continuous wave laser. The output-input power characteristics and nonlinear transmission properties for different solutions of copper phthalocyanine and polychloro copper phthalocyanine in acetone at increasing concentration were obtained. The observed nonlinearities were interpreted theoretically by rate-equation within a three-level model. The good optical limiting performance is attributed to a reverse saturable absorption (RSA) mechanism. It indicates that both copper phthalocyanine and polychloro copper phthalocyanine could be promising candidates for optical limiting materials. (c) 2009 Elsevier B.V. All rights reserved.