CAJ | 학술논문

在常规型有机发光二极管的基础上,通过改变发光层tri-(8-hydroxyquinoline) aluminum (III)(Alq3)厚度,研究了激子复合区厚度对有机发光二极管磁效应的影响.测量了器件在不同温度及偏压下电致发光及注入电流在外加磁场作用下的变化,着重研究了低温下的有机磁电导效应和有机磁电致发光效应.实验发现,低温(50 K)高磁场(500 mT)下,器件表现出随Alq3厚度的减薄,磁电导值由正到负再到正的非单调变化.利用磁场调控的超精细相互作用、磁场抑制的三重态激子-电荷反应以及激子在界面的淬灭效应,对有机磁电导在低温下表现出的现象进行了定性的解释.实验结果表明,通过改变激子复合区的厚度,可以实现对激子浓度的有效调节,进而实现对有机磁电导和磁电致发光效应的调节.该研究进一步丰富了有机磁效应的实验现象,同时提供了一种调控有机磁效应的手段.
재상규형유궤발광이겁관적기출상,통과개변발광층tri-(8-hydroxyquinoline) aluminum (III)(Alq3)후도,연구료격자복합구후도대유궤발광이겁관자효응적영향.측량료기건재불동온도급편압하전치발광급주입전류재외가자장작용하적변화,착중연구료저온하적유궤자전도효응화유궤자전치발광효응.실험발현,저온(50 K)고자장(500 mT)하,기건표현출수Alq3후도적감박,자전도치유정도부재도정적비단조변화.이용자장조공적초정세상호작용、자장억제적삼중태격자-전하반응이급격자재계면적쉬멸효응,대유궤자전도재저온하표현출적현상진행료정성적해석.실험결과표명,통과개변격자복합구적후도,가이실현대격자농도적유효조절,진이실현대유궤자전도화자전치발광효응적조절.해연구진일보봉부료유궤자효응적실험현상,동시제공료일충조공유궤자효응적수단.
@@@@In this work we explore the influence of the exciton recombination zone (RZ) on magnetic-field effect in tris-(8-hydroxyquinolinato) aluminum (Alq3) based organic light-emitting diodes by changing the thickness of Alq3. The magneto-electroluminescence and magneto-conductance (MC) in these devices are investigated at various temperatures and bias voltages. It is found that the sign of MC changes from positive to negative, and then back to positive with the reduction of the thickness of Alq3 at 50 K. The phenomenon observed is ascribed to the change of the exciton density in the exciton RZ. Based on the mechanisms including the hyperfine mixing, the triplet-charge interaction and interfacial dissociation or quenching of excitons, the observed results are explained qualitatively.