화학공학소재연구정보센터
Chemical Physics Letters, Vol.501, No.4-6, 572-574, 2011
Two-photon excitation of 2,5-diphenyloxazole using a low power green solid state laser
This Letter concerns two-photon excitation of 2,5-Diphenyloxazole (PPO) upon illumination from a pulsed 532 nm solid state laser, with an average power of 30 mW, and a repetition rate of 20 MHz. A very agreeable emission spectrum position and shape has been achieved for PPO receiving one-and two-photon excitation, which suggests that the same excited state is involved for both excitation modes. Also, a perfect quadratic dependence of laser power in the emission intensity function has been recorded. We tested the application of a small solid state green laser to two-photon induced time-resolved fluorescence, revealing the emission anisotropy of PPO to be considerably higher for two-photon than for one-photon excitation. (C) 2010 Elsevier B.V. All rights reserved.