本論文主要探討並四苯中單重激發態分子的裂變機制之光電流磁電導效應，發現在具有強烈單重激發態分子裂變機制的並四苯材料中，此機制會受到磁場所影響並反應至磁電導效應中，而可以藉由改變元件結構來調變其中之機制。磁電導效應會受到外加電場的作用、摻雜其他材料、施體與受體之間介面的產生而有所改變－在摻雜C60進入並四苯中，C60本身的磁電導效應會開始與其競爭，使得分別表現出單重激發態分子裂變或是C60的磁電導效應。另外在介面產生時，則必須多考慮三重態激發子與載子之反應(Triplet charge reaction)所造成的磁電導影響。而材料中缺陷態的產生則會使得元件在電性的上的貢獻有所改變。由上述結果中，我們認為單重激發態分子的裂變為一反應很快的機制，因此不管改變元件構造、摻雜C60、介面產生，仍然可以觀察到其所貢獻的磁電導效應，只是其他的磁電導效應會開始與其競爭並有所影響。

We have investigated the mechanisms of singlet fission in magneto conductance (MC) responses of tetracene-based diodes. Strong singlet fission is found in Tetracene, which will be affected by the magnetic field and results in magneto conductance. The MC will be affected by applying bias voltage, doping another material, producing interface between donor and accepter. We found that once the C60 was doped into Tetracene, the MC of C60 will appear and start competing with the MC of single fission. Furthermore, MC caused by triplet charge reaction should also be considered when the interfaces emerge. Based on the discussion above, we believe that singlet fission is a very fast reaction, no matter the changes in devices structure, emerge of surface, or varying in thickness, the MC which is contributed by singlet fission can still be observed, the only difference is the effect will start competing with other mechanisms.

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