title: Magneto-conductance characteristics of trapped triplet-polaron and triplet-trapped polaron interactions in anthracene-based organic light emitting diodes.
abstract: The effects of a magnetic field on the dissociation of triplet excitons by free charges (TCI) are well understood. However, the magneto-conductance (MC) characteristics of trapped triplet-polaron interactions (TtPI) and triplet-trapped polaron interactions (TPtI) within organic light emitting diodes (OLEDs) are not well understood. We have studied these interactions in an anthracene-based OLED. The electroluminescence spectra, current-voltage characteristics and magneto-electroluminescence indicated that the anthracene layer contained many defects that could trap either triplet excitons or polarons, which led to TPtI and TtPI. The MC curves at low temperature exhibited a complex line shape, which indicated that intersystem crossing, TPtI, TtPI, and TCI occurred simultaneously in the device. The individual MC characteristics of TPtI and TtPI were extracted from temperature dependant MC curves by fitting them to three empirical Lorentzian functions and one non-Lorentzian function. The MC of TPtI exhibited a negative sign, while that of TtPI exhibited a positive one, with characteristic magnetic fields (B0) of ∼10.5 and ∼15 mT, respectively. Both processes were prominent below 150 K and weakened with increasing temperature. TPtI was neglected above 200 K, while TtPI was observed even at ambient temperature. These results add significant insight into the magnetic field effects on triplet-polaron interactions.
authors: School of Physical Science and Technology, MOE Key Laboratory on Luminescence and Real-Time Analysis, Southwest University, Chongqing 400715, People's Republic of China. zhxiong@swu.edu.cn.
authors: Weiyao
authors: W
authors: Jia
authors: Department of Materials Science, Fudan University, Shanghai, 200433, People's Republic of China.
authors: Qiusong
authors: Q
authors: Chen
authors: School of Physical Science and Technology, MOE Key Laboratory on Luminescence and Real-Time Analysis, Southwest University, Chongqing 400715, People's Republic of China. zhxiong@swu.edu.cn.
authors: Yingbing
authors: Y
authors: Chen
authors: School of Physical Science and Technology, MOE Key Laboratory on Luminescence and Real-Time Analysis, Southwest University, Chongqing 400715, People's Republic of China. zhxiong@swu.edu.cn.
authors: Lixiang
authors: L
authors: Chen
authors: School of Physical Science and Technology, MOE Key Laboratory on Luminescence and Real-Time Analysis, Southwest University, Chongqing 400715, People's Republic of China. zhxiong@swu.edu.cn.
authors: Zuhong
authors: Z
authors: Xiong