Luchowski Rafal
Center for Commercialization of Fluorescence Technologies (CCFT), Department of Molecular Biology and Immunology, UNTHSC, Fort Worth, TX 76107, USA.
Chem Phys Lett. 2011 Jan 7;501(4-6):572-574. doi: 10.1016/j.cplett.2010.11.038.
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.
本信函涉及用平均功率为30 mW、重复频率为20 MHz的脉冲532 nm固态激光器照射时，2,5-二苯基恶唑（PPO）的双光子激发。对于接受单光子和双光子激发的PPO，已获得非常合适的发射光谱位置和形状，这表明两种激发模式涉及相同的激发态。此外，还记录到发射强度函数中激光功率的完美二次依赖性。我们测试了小型固态绿色激光器在双光子诱导时间分辨荧光中的应用，结果表明，与单光子激发相比，PPO在双光子激发下的发射各向异性要高得多。
