本實驗研究有機並四苯摻雜富勒烯C60的磁電導效應。而磁電導效應與激發態濃度有相對關係，因此藉由摻混富勒烯C60來分析激發態濃度對於磁電導效應的影響。首先觀察到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。隨著富勒烯C60的加入，發現到磁電導效應的趨勢會完全改變。從實驗中得到，改變摻混富勒烯C60的濃度可驗證出富勒烯C60本身的磁電導效應會與之競爭，而影響原裂變機制所貢獻的磁電導。另外，光電流的生成可影響自由載子數量，此時三重態激發子有機會與載子反應(Triplet charge reaction)而貢獻出負磁電導效應。以上為富勒烯C60摻雜對並四苯磁電導效應的影響。

The purpose of this study is to identify magneto-conductance (MC) under illumination in tetracene blend fullerene C60 organic diodes. Due to the closely correlation between MC and the concentration of the excited states, we control the concentration of excited state by blending C60 into tetracene. First, we found strong singlet fission in tetracene, which could be affected by the magnetic field and results in magneto-conductance. However, we detected the characteristic of MC will be varied from adding the C60. With increasing the concentration of the C60, the positive MC of C60 will appear and eventually replace the MC of single fission. In addition, the negative MC were obtained if the devices had numerous free carriers will react with triplet excitons. Then the triplet charge reaction will decreased with applied magnetic field contributing to a negative MC component. Our results demonstrate these influence by doping C60 will compete with the magneto-conductance related to singlet fission.

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