Emergence of fifth-order optical nonlinearity in 2-(2-Quinolyl)-1,3-indandione with strong third-order nonlinear effect under low power CW laser excitation

The present work reports the presence of fifth-order optical nonlinearity in 2-(2-Quinolyl)-1,3-indandione, an organic dye, at low intensity level. Photophysical, structural and vibrational properties were studied by theoretical and experimental methods. Z-scan study of the dye revealed that the compound has a self-defocusing behaviour at continuous Nd:YAG 532 nm laser excitation and exhibited reverse saturable absorption. The positive fifth-order nonlinear refractive index (n4) is of the order of 10-10 cm4/W2. The nonlinearities present in the compound has both thermal and electronic origin. This study reveals that the material is a potential candidate as an optical limiter at low power.

Automated summary

The study investigates the fifth-order optical nonlinearity in an organic dye at low intensity level, revealing a positive fifth-order nonlinear refractive index. The compound exhibits self-defocusing behavior under specific laser excitation, making it a potential candidate for an optical limiter at low power. The nonlinearities in the compound have both thermal and electronic origins, as shown by theoretical and experimental methods.