Three-photon-absorption-induced frequency-upconversion fluorescence emission has been observed in a solution of 2,5-benzothiazole 3,4-didecyloxy thiophene (BBTDOT) in tetrahydrofuran, pumped with 10-ns Q-switched 1.06-μm laser pulses. The spectral peak of the observed fluorescence emission is located in the 450–480-nm range, and the intensity dependence of the visible emission on the IR excitation obeys the cubic law. At a higher solute concentration (0.18 M/L) and moderate IR excitation intensity levels (50–200 MW/cm2), obvious optical limiting behavior has been observed as a result of three-photon absorption. The measured nonlinear absorption coefficient and the corresponding molecular three-photon-absorption cross section are γ = 2.7 × 10−18 cm3/W2 and , respectively.
© 1995 Optical Society of AmericaFull Article | PDF Article
Guang S. He, Bruce A. Reinhardt, Jay C. Bhatt, Ann G. Dillard, Gen C. Xu, and Paras N. Prasad
Opt. Lett. 20(5) 435-437 (1995)
Guang S. He, Lixiang Yuan, Ning Cheng, Jayant D. Bhawalkar, Paras N. Prasad, Lawrence L. Brott, Stephen J. Clarson, and Bruce A. Reinhardt
J. Opt. Soc. Am. B 14(5) 1079-1087 (1997)
Guang S. He, Tzu-Chau Lin, Paras N. Prasad, Ramamurthi Kannan, Richard A. Vaia, and Loon-Seng Tan
Opt. Express 10(13) 566-574 (2002)