Optical nonlinearity in a mode-locking dye: optical limiting and four wave mixing

✍ Scribed by G.Ravindra Kumar; F.A. Rajgara; S.A. Rangwala

• Publisher: Elsevier Science
• Year: 1995
• Tongue: English
• Weight: 353 KB
• Volume: 245
• Category: Article
• ISSN: 0009-2614
• DOI: 10.1016/0009-2614(95)01007-v

✦ Synopsis

We report the optical nonlinearity resonantly induced by picosecond laser excitation in Kodak 9740 mode-locking dye. The observed nonlinearity is due to the participation of high-lying singlet states. The specific processes studied are optical limiting and phase conjugation. We infer that the mechanism underlying the limiting behaviour is due to two-photon absorption, and obtain a value for the two-photon absorption coefficient /3. Further, we report the intensity dependence of the phase conjugate signal and obtain the corresponding third-order susceptibility.