超小磁场下Rubrene电致发光磁效应的演化

发布时间：2018-03-04 06:10

本文选题：红荧烯　切入点：超小磁场　出处：《中国科学:技术科学》2017年01期 　论文类型：期刊论文

【摘要】：制备了基于5,6,11,12-tetraphenylnaphthacene(Rubrene)的有机发光二极管,并测量器件在不同偏压与工作温度下电致发光的磁场效应(magneto-electroluminescence,MEL).实验发现:在室温下,MEL曲线在零磁场附近几毫特斯拉范围内为W线型;而当温度降低到75 K左右,该W线型消失,MEL却呈现出一种新的精细结构,即M型的超小场效应,这种演化过程在以前的文献中未见报道.分析表明:室温下MEL的W线型是极化子对(polaron pair,PP)的超精细相互作用和外磁场引起的塞曼作用对载流子自旋共同调控的结果;低温下MEL的M线型与三重态-三重态激子湮灭(triplet-triplet annihilation,TTA)过程相关,可以用零场劈裂与塞曼作用对三重态激子对(triplet pair state,(TT)i)演化过程的共同调控来解释.该发现不仅丰富了有机半导体中的磁现象,而且加深了对有机发光器件中激发态间自旋相互作用的认识.
[Abstract]:The organic light-emitting diodes (OLEDs) based on 5HY611111-tetraphenylnaphthacene (Rubrene) were prepared, and the magneto-electroluminescent magneto-electroluminescence (Mel) curves were measured at different bias voltages and working temperatures. The experimental results show that the Mel curves are W line in the range of several nano#china_person0# near zero magnetic field at room temperature. However, when the temperature decreases to about 75 K, the W-shape vanishing Mel presents a new fine structure, that is, the ultra-small field effect of M-type. This evolution process has not been reported in previous literatures. The analysis shows that the W line of MEL at room temperature is the result of hyperfine interaction between polaron pairn and Zeeman interaction induced by external magnetic field on the carrier spin. The M-lineform of MEL at low temperature is related to the triplet-triplet annihilation of excitons (triplet-triplet). It can be explained by the co-regulation of zero-field splitting and Zeeman interaction on the evolution of triplet pair state in triplet excitons. This discovery not only enriches the magnetic phenomena in organic semiconductors. Furthermore, the spin interaction between excited states in organic luminescent devices is well understood.
【作者单位】：西南大学物理科学与技术学院;
【基金】：国家自然科学基金(批准号:11374242)资助项目
【分类号】：TN383.1

【相似文献】