本研究是利用光致吸收(Photo-induced absorption PA)的技術來研究有機共軛高分子在摻雜過渡金屬化合物之後的三重態激子的改變，藉由摻雜10%重量百分濃度的Ｉr(mppy)3　在PFO中，我們發現100K溫度下PFO的三重態激子在摻雜後數量約為原來的10倍，平均生命期約為原來的十分之ㄧ，並推論出在摻雜10%重量百分濃度Ｉr(mppy)3的情形下PFO的內系統跨越(inter-system crossing)效率將可增大2個數量級，我們更進ㄧ步針對不同濃度和不同溫度下觀察PFO三重態激子的改變，從實驗結果中，我們推論PFO三重態激子的改變來自於Ir(mppy)3的重原子效應。

We use photo-induced absorption technique to investigate the change of the triplet excitons in conjugated polymer doped with transition-metal complexes. By comparing pure PFO with PFO doped with 10 wt% Ir(mppy)3, we find the population of the triplet excitons in PFO doped with 10 wt% Ir(mppy)3 increases by one order of magnitude. The average lifetime of the triplet excitons in PFO doped with 10 wt% Ir(mppy)3 decreases by one order of magnitude. Combining these two results and the measurement of photoluminescence quantum efficiency, we deduce that the rate constant of the inter-system crossing increases by two order of magnitude after doping with 10 wt% Ir(mppy)3 . Furthermore, we compare the results at different concentrations and different temperature. In accordance with our experimental results, we deduce that the change of the triplet excitons in PFO comes from heavy-atom effect from Ir(mppy)3.

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