Nonlinear optical properties of meso-substituted porphyrins using spatial self-phase modulation

Herein, we studied the nonlinear optical properties of four meso-substituted porphyrins (H 2 MHTPP, H 2 THTPP, H 2 DETPP, and H 2 TETPP) by the spatial self-phase modulation (SSPM) method, using CW lasers with wavelengths of 532 nm and 780 nm. All samples exhibit strong nonlinear response due to the thermal optical nonlinear effect at 532 nm, which corresponds to the strong absorption band. In addition, four porphyrin samples were calculated that have nonlinear refractive index coefficients of the same order of magnitude (10 −10 m 2 /W) at 532 nm. However, four porphyrins exhibited different optical nonlinear responses affected by the type and numbers of peripheral substituents at 780 nm. This work is of significance for reasonably adjusting the structure of compounds and improving their third-order nonlinear optical coefficients.