A Quantitative Theory Model of a Photobleaching Mechanism
摘要
A photobleaching model: D-P (dye-photon interaction) and D-O (Dye-oxygen oxidative reaction) photobleachingtheory, is proposed. The quantitative power dependences of photobleaching rates with both one- and two-photonexcitations (1 PE and TPE) are obtained. This photobleaching model can be used to elucidate our and otherexperimental results commendably. Experimental studies of the photobleaching rates for rhodamine B withTPE under unsaturation conditions reveals that the power dependences of photobleaching rates increase withthe increasing dye concentration, and that the photobleaching rate of a single molecule increases in the secondpower of the excitation intensity, which is different from the high-order (> 3) nonlinear dependence of ensemblemolecules.