3RD-ORDER NONLINEAR-OPTICAL INTERACTIONS IN TETRABENZPORPHYRINS

Third-order nonlinear optical susceptibility chi(3) was measured for a variety of tetra-benzporphyrin compounds in solution in tetrahydrofur an at 532 nm using the technique of degenerate four-wave mixing. High values in the range 10(-9) to 10(-8) esu are observed. The dominant co ntribution comes from the imaginary part as a result of excited state absorption. Measurements were also made on thin films, deposited by th e Langmuir-Blodgett technique, for one of the compounds. Mirrorless al l-optical bistability induced by reverse saturable absorption was obse rved. These materials are good candidates for some applications in pho tonics technology.