Thin films of novel nonlinear organic materials

Several recent studies have shown that organic materials can be promising for nonlinear optics due to their large nonlinearities as well as resistance to optical damage. From our investigation of a number of new compounds, three materials with a nonlinearity larger than urea by an order of magnitude, are shown in Fig. 1. These compounds, 1-(2,4-dimitrophenyl)-semicarbazide, 3-dimethylamino-4′-nitroacrylophenone, and di-(p-nitrophenyl)urea, also, showed no sign of damage at power densities up to 0.25 GW/cm2 from a Q-switched Nd:YAG laser. In comparison, a powder sample of LiNbO3 was readily damaged at an intensity of 10 MW/cm2.